TW202242518A - Electrochromic devices, the precursor thereof, and method and apparatus of fabricating the same - Google Patents

Abstract

Conventional electrochromic devices frequently suffer from poor reliability and poor performance. Improvements are made using entirely solid and inorganic materials. Electrochromic devices are fabricated by forming an ion conducting electronically insulating interfacial region that serves as an IC layer. In some methods, the interfacial region is formed afterformation of an electrochromic and a counter electrode layer. The interfacial region contains an ion conducting electronically insulating material along with components of the electrochromic and/or the counter electrode layer. Materials and microstructure of the electrochromic devices provide improvements in performance and reliability over conventional devices.

Description

Electrochromic device, its precursor and method and equipment for its manufacture

The present invention relates to an electrochromic device, a precursor of the electrochromic device, and a method and equipment for manufacturing the electrochromic device.

Electrochromism is a phenomenon in which a material exhibits a reversible, electrochemically mediated change in optical properties when placed in a different electronic energy state, usually by being subjected to a voltage change. Optical properties are typically one or more of color, transmittance, absorbance, and reflectance. For example, one well-known electrochromic material is tungsten oxide (WO ₃ ). Tungsten oxide is a cathodic electrochromic material in which the color transition (blue transmission) occurs by electrochemical reduction. Electrochromic materials can be incorporated into, for example, windows and mirrors. The tint, transmittance, absorbance and/or reflectance of these windows and mirrors can be changed by inducing changes in the electrochromic material. For example, one well-known application of electrochromic materials is in some automobile mid-view mirrors. In these electrochromic rearview mirrors, the reflectivity of the mirror changes at night so that the headlights of other vehicles do not distract the driver. Despite the discovery of the electrochromic system in the 1960's, unfortunately, electrochromic devices still suffer from various problems and have not yet begun to realize their full commercial potential. There is a need for advances in electrochromic technology, devices, and related methods of making and/or using such devices.

A typical electrochromic device includes an electrochromic ("EC") electrode layer and a counter electrode ("CE") layer separated by an ion-conducting ("IC") layer that is highly conductive to ions and highly resistant to electrons. In other words, the ionically conductive layer permits transport of ions but blocks electrical current. As generally understood, the ion-conducting layer thus prevents short circuits between the electrochromic layer and the counter electrode layer. The ion-conducting layer allows the electrochromic electrode and counter electrode to retain charge, and thereby maintain their faded or colored state. In conventional electrochromic devices, the components form a stack with the ion-conducting layer sandwiched between the electrochromic electrode and the counter electrode. The boundaries between these three stacked components are defined by abrupt changes in composition and/or microstructure. Thus, the devices have three distinct layers with two abrupt interfaces. Quite surprisingly, the inventors have discovered that high quality electrochromic devices can be fabricated without depositing an ion-conducting electrically insulating layer. According to a particular embodiment, the counter electrode and the electrochromic electrode are formed in close proximity to each other (often in direct contact) without separately depositing the ion-conducting layer. It is believed that various fabrication procedures and/or physical or chemical mechanisms create an interfacial region between the contacting electrochromic layer and the counter electrode layer, and that this interfacial region acts as at least some of the ion-conducting electrically insulating layers in conventional devices Function. Specific mechanisms that may be key to the formation of the interfacial region are described below. The interfacial region typically, though not necessarily, has a heterostructure comprising at least two discrete components represented by different phases and/or compositions. Additionally, the interfacial region may include gradients among these two or more discrete components. The gradient can provide, for example, variable composition, microstructure, resistivity, dopant concentration (eg, oxygen concentration), and/or stoichiometry. In addition to the above findings, the inventors have also observed that in order to improve device reliability, the two layers of an electrochromic device (the electrochromic (EC) layer and the counter electrode (CE) layer) can be fabricated so that each includes Lithium in defined quantities. Additionally, careful selection of materials and morphology and/or microstructure of some components of an electrochromic device provides improvements in performance and reliability. In some embodiments, all layers of the device are solid and inorganic. Consistent with the above observations and findings, the inventors have discovered that the formation of the EC-IC-CE stack does not need to proceed in the conventional sequence (EC→IC→CE or CE→IC→EC), but can be done in the electrochromic layer and the opposite Formation of the electrode layer is followed by the formation of an ionically conductive electrically insulating region that acts as the IC layer. That is, first an EC-CE (or CE-EC) stack is formed, then a stack is formed between the EC layer and the CE layer at the interface of the EC layer and the CE layer using components of either or both of these layers. To the interface area of IC layer for some purposes. The method of the present invention not only reduces manufacturing complexity and cost by eliminating one or more processing steps, but also provides devices exhibiting improved performance characteristics. Therefore, one aspect of the present invention is a method of manufacturing an electrochromic device, the method comprising: forming an electrochromic layer including an electrochromic material; forming a counter electrode layer in contact with the electrochromic layer, and without first providing an ionically conductive electrically insulating layer between the electrochromic layer and the counter electrode layer; and forming an interface region between the electrochromic layer and the counter electrode layer, wherein the interface region is substantially ionic Conductive and substantially electrically insulating. The electrochromic layer and the counter electrode layer are typically (but not necessarily) made of one or more materials that are more conductive than the interfacial region but may have some electron-resistant properties. The interfacial region can contain constituent materials of the EC layer and/or the CE layer, and in some embodiments, the EC layer and the CE layer contain constituent materials of the interfacial region. In one embodiment, the electrochromic layer includes WO ₃ . In some embodiments, the EC layer includes WO ₃ , the CE layer includes nickel tungsten oxide (NiWO), and the IC layer includes lithium tungstate (Li ₂ WO ₄ ). Heating may be applied during deposition of at least a portion of the electrochromic layer. In one embodiment, where the EC layer comprises WO ₃ , heating is applied after each of a series of depositions by sputtering in order to form an EC layer with a substantially polycrystalline microstructure. In one embodiment, the thickness of the electrochromic layer is between about 300 nm and about 600 nm, but the thickness can vary depending on the desired result of forming the interfacial region expected after depositing the EC-CE stack. In some embodiments, WO ₃ is substantially polycrystalline. In some embodiments, an oxygen-rich layer of WO ₃ may be used as a precursor to the interfacial region. In other embodiments, the WO ₃ layer is a graded layer with varying oxygen concentration in the layer. In some embodiments, lithium is the preferred ion species for driving the electrochromic transition, and a stack or layer lithiation scheme is described. Details of the formation parameters and layer properties are described in more detail below. Another aspect of the present invention is a method of manufacturing an electrochromic device, the method comprising: (a) forming an electrochromic layer comprising an electrochromic material or a counter electrode layer comprising a counter electrode material; (b) An intermediate layer is formed over the electrochromic layer or the counter electrode layer, wherein the intermediate layer includes an oxygen-enriched form of at least one of the electrochromic material, the counter electrode material, and an additional material, wherein the additional material comprising a dissimilar electrochromic material and/or counter electrode material, the intermediate layer is not substantially electrically insulating; (c) forming the other of the electrochromic layer and the counter electrode layer; and ( d) allowing at least a portion of the intermediate layer to become substantially electrically insulating and substantially ionically conductive. Details of the formation parameters and layer characteristics used in this method will also be described in more detail below. Another aspect of the present invention is an apparatus for fabricating an electrochromic device comprising: an integrated deposition system comprising: (i) a first deposition station containing a source of material configured to deposit materials including electrochromic an electrochromic layer of a color-changing material; and (ii) a second deposition station configured to deposit a counter electrode layer comprising a counter electrode material; and a controller containing a transfer the substrate through the program instructions of the first deposition station and the second deposition station, the stack has an intermediate layer sandwiched between the electrochromic layer and the counter electrode layer; wherein the first deposition station and the Either or both of the second deposition stations are also configured to deposit the intermediate layer over the electrochromic layer or the counter electrode layer, and wherein the intermediate layer includes the electrochromic material or the counter electrode material and wherein the first deposition station and the second deposition station are interconnected in series and are operable to transfer a substrate from one station to the next without exposing the substrate to the external environment. In one embodiment, the apparatus of the present invention is operable to transfer the substrate from one station to the next without breaking vacuum, and may include operable to deposit lithium from a source of lithium-containing material on the electrochromic device. One or more lithiation sites on one or more layers. In one embodiment, the apparatus of the present invention is operable to deposit the electrochromic stack on an architectural glass substrate. The apparatus of the present invention need not have a separate target for making the ion-conducting layer. Another aspect of the present invention is an electrochromic device comprising: (a) an electrochromic layer comprising an electrochromic material; (b) a counter electrode layer comprising a counter electrode material; and (c) an electrochromic layer comprising an electrochromic material; The interface region between the electrochromic layer and the counter electrode layer, wherein the interface region includes an electrically insulating ion-conducting material and at least one of the electrochromic material, the counter electrode material, and an additional material, wherein the Additional materials include dissimilar electrochromic materials and/or counter electrode materials. In some embodiments, the additional material is not included; in these embodiments, the interface region includes at least one of the electrochromic material and the counter electrode material. Variations in the composition and morphology and/or microstructure of the interfacial region are described in more detail herein. The electrochromic devices described herein can be incorporated into windows (in one embodiment, architectural glass scale windows). These and other features and advantages of the present invention will be described in more detail below with reference to the associated drawings.

This application claims the benefit and priority of U.S. Application Nos. 12/772,055 and 12/772,075, each filed April 30, 2010, and entitled "Electrochromic Devices," which applications Each of which is incorporated by reference in its entirety. The following detailed description can be more fully understood when considered in conjunction with the accompanying drawings. FIG. 1A is a schematic cross-section depicting a conventional electrochromic device stack 100 . The electrochromic device 100 includes a substrate 102 , a conductive layer (CL) 104 , an electrochromic (EC) layer 106 , an ion conducting (IC) layer 108 , a counter electrode (CE) layer 110 and a conductive layer (CL) 112 . Elements 104 , 106 , 108 , 110 , and 112 are collectively referred to as electrochromic stack 114 . Typically, these CL layers are made of transparent conductive oxides and are often referred to as "TCO" layers. Since the TCO layer is transparent, the coloring behavior of the EC-IC-CE stack can be observed, for example, through the TCO layer, allowing the use of these devices on windows for reversible shading. A voltage source 116 operable to apply a potential across the electrochromic stack 114 effects the transition of the electrochromic device from, for example, a faded state (ie, transparent) to a colored state. The order of the layers can be reversed with respect to the substrate. That is, the layers may be in the following order: substrate, transparent conductive layer, counter electrode layer, ion-conducting layer, electrochromic material layer and (another) transparent conductive layer. Referring again to FIG. 1A , in a conventional method of fabricating an electrochromic stack, individual layers are deposited on top of one another in a sequential format as depicted in the schematic diagram on the left side of FIG. 1A . That is, the TCO layer 104 is deposited on the substrate 102 . Next, an EC layer 106 is deposited on the TCO 104 . Next, an IC layer 108 is deposited on the EC layer 106 , followed by a CE layer 110 deposited on the IC layer 108 , and finally a TCO layer 112 deposited on the CE layer 110 to form the electrochromic device 100 . Of course, the order of the steps can be reversed to form a "reverse" stack, but the point is that in conventional methods, the IC layer must be deposited on the EC layer followed by the CE layer deposited on the IC layer, or the IC layer deposited on the On the CE layer, followed by the EC layer is deposited on the IC layer. The transitions between layers of material in the stack are abrupt. One of the significant challenges of the above process is the processing required to form the IC layer. In some previous approaches, the IC layer was formed by a sol-gel process that was difficult to incorporate into the CVD or PVD processes used to form the EC and CE layers. Furthermore, IC layers produced by sol-gel and other liquid-based processes are prone to have defects that degrade the quality of the device and may need to be removed by, for example, engraving. In other approaches, IC layers are deposited by PVD from ceramic targets which can be difficult to manufacture and use. 1B is a graph depicting material % composition versus position in the electrochromic stack of FIG. 1A (ie, layers 106, 108, and 110, ie, the EC layer, the IC layer, and the CE layer). As mentioned, in conventional electrochromic stacks, the transitions between material layers in the stack are abrupt. For example, EC material 106 is deposited as a distinct layer with little or no composition bleed to adjacent IC layers. Similarly, IC material 108 and CE material 110 are compositionally distinct with little or no percolation to adjacent layers. Thus, these materials are substantially homogeneous (except for certain compositions of CE materials described below) and have abrupt interfaces. The conventional thinking is that each of the three layers should be laid down as distinct uniformly deposited and smooth layers to form a stack. The interface between each layer should be "clear" where there is little intermingling of materials from each layer at the interface. Those of ordinary skill in the art will recognize that FIG. 1B is an idealized depiction and that, in a practical sense, there is a certain degree of unavoidable mixing of materials at the layer interfaces. The point is that any such mixing is unintentional and minimal in conventional manufacturing methods. The inventors have discovered that an interfacial region can be formed that acts as an IC layer, wherein the interfacial region intentionally includes a substantial amount of one or more electrochromic materials and/or counter electrode materials. This is a fundamental departure from known manufacturing methods. As mentioned above, the inventors have discovered that the formation of the EC-IC-CE stack does not have to be done in the conventional sequence (EC→IC→CE or CE→IC→EC), but can be done between the electrochromic layer and the opposing Deposition of the electrode layers is followed by the formation of an interfacial region that acts as an ion-conducting layer. That is, the EC-CE (or CE-EC) stack is formed first, then the layers (and/or another electrochromic material or counter electrode material in some embodiments) are applied at the interface of the layers ) form an interfacial region (which may possess at least some of the functions of the IC layer) between the EC layer and the CE layer. The interfacial region serves at least some of the functions of conventional IC layers in that the interfacial region is substantially ionically conductive and substantially electrically insulating. It should be noted, however, that the interfacial region as described may have leakage currents higher than conventionally accepted leakage currents, but nevertheless these devices show good performance. In one embodiment, the electrochromic layer is formed with an oxygen-rich region that, after deposition of the counter electrode layer, is converted to act as an interfacial region or layer of the IC layer in subsequent processing. In some embodiments, a dissimilar layer comprising an oxygen-rich version of the electrochromic material is used to (eventually) form an interface layer between the EC layer and the CE layer that acts as the IC layer. In other embodiments, a dissimilar layer comprising an oxygen-rich version of the counter electrode material is used to (eventually) form an interfacial region between the EC layer and the CE layer that acts as the IC layer. All or part of the oxygen-enriched CE layer is converted into an interfacial region. In other embodiments, a distinct layer comprising an oxygen-enriched version of the counter electrode material and an oxygen-enriched version of the electrochromic material is used to (eventually) form an interfacial region between the EC layer and the CE layer that acts as the IC layer. In other words, some or all of the oxygen-rich material acts as a precursor to the interfacial region of the IC layer. The method of the present invention not only reduces processing steps, but also results in electrochromic devices exhibiting improved performance characteristics. As mentioned, it is believed that some of the EC layer and/or CE layer in the interfacial region is converted to provide one or more functions of the IC layer (in particular high conductivity for ions and high resistivity for electrons) The material. The IC functional material in the interfacial region can be, for example, a salt of a conductive cation; for example, a lithium salt. 2A, 2B, and 2C show compositional graphs for three possible examples of electrochromic device stacks (each containing an EC layer, a CE layer, and an interfacial region serving as an IC layer), where the EC material is tungsten oxide (here denoted is WO ₃ , but is intended to include WO _x , where x is between about 2.7 and about 3.5, and in one embodiment, x is between about 2.7 and about 2.9), the CE material is nickel tungsten oxide (NiWO), and the interface The region mainly comprises lithium tungstate (represented here as Li ₂ WO ₄ , in another embodiment, the interfacial region is between about 0.5% and about 50 (atomic) % Li ₂ O, between about 5% and about _A nanocomposite of between 95% _Li2W04 and between about ₅ % and about 70% WO3) and some amount of EC material and/or CE material. More generally, an interfacial region typically, but not necessarily, has a heterostructure comprising at least two discrete components represented by distinct phases and/or compositions whose concentrations vary across the width of the interfacial region. For this reason, the interfacial region serving as the IC layer is sometimes referred to herein as a "gradient region," a "heterogeneous IC layer," or a "distributed IC layer." Although described with respect to specific materials, the illustrations in Figures 2A, 2B, and 2C more generally represent variations in the composition of any suitable material for electrochromic devices of the present invention. Figure 2A depicts an electrochromic stack of the present invention where the EC material is an important component serving as the interfacial region of the IC layer and the CE material is not. Referring to FIG. 2A , starting from the origin and moving from left to right along the x -axis, one can see that a portion of the EC material WO ₃ , which is substantially all tungsten oxide, acts as the EC layer. There is a transition into the interfacial region where there is progressively less tungsten oxide and correspondingly more lithium tungstate up to and including near the end of the interfacial region where there is a substantial amount of tungsten oxide with some minimum amount All of the above are parts of lithium tungstate. Although the transition from the EC layer to the interfacial region is distinguished by a composition of substantially all tungsten oxide and a minimal amount of lithium tungstate, it is apparent that the transition is not as abrupt as in conventional devices. In this example, in fact, the transition begins with the composition having a sufficient amount of lithium tungstate to enable the material to perform at least some of the functions of the IC layer, such as ion conduction and electrical insulation. Undoubtedly, compositions closer to the CE layer, where the composition is essentially lithium tungstate, function as the IC layer, since lithium tungstate is known to exhibit such properties. But there is also some IC layer function in other parts of the interface region. The inventors have found that such "heterogeneous IC layers" improve the switching characteristics and possibly thermal cycling stability of electrochromic devices compared to conventional devices with abrupt transitions. The CE layer in this example mainly contains nickel-tungsten oxide as the active material, with a relatively abrupt transition to the nickel-tungsten oxide composition at the edge of the interfacial region. Methods for fabricating stacks with such interfacial regions are described in more detail below. It should be noted, for example, that the nickel tungsten oxide CE layer in FIG. 2A is depicted as having about 20% lithium tungstate. Without wishing to be bound by theory, it is believed that the nickel tungsten oxide CE layer exists as nickel oxide cores or particles (which impart fairly good ionic conductivity to the CE layer) surrounded by a shell or matrix of lithium tungstate, and thereby in The electrochromic transition of the CE layer is aided during operation of the electrochromic stack. The exact stoichiometry of lithium tungstate in the CE layer can vary significantly between embodiments. In some embodiments, some tungsten oxide may also be present in the CE layer. Also, because lithium ions travel to and from the EC and CE layers through the interfacial region that acts as the IC layer, there may be a significant amount of lithium tungstate in the EC layer, eg, as depicted in Figure 2A. Figure 2B depicts the electrochromic stack of the present invention, where the CE material is an important component serving as the interfacial region of the IC layer, while the EC material is not. Referring to Figure 2B, starting from the origin and moving from left to right along the x -axis, one can see that in this case the EC material, substantially all tungsten oxide, serves as the EC layer. There is an abrupt transition into the interfacial region where there is little, if any, tungsten oxide but a lot of lithium tungstate and at least some nickel tungsten oxide (CE material). The composition of the interfacial region varies along the x -axis with decreasing amounts of lithium tungstate and corresponding increasing amounts of nickel tungsten oxide. The transition from the interfacial region to the CE layer is arbitrarily distinguished by a composition of about 80% nickel tungsten oxide and about 20% lithium tungstate, but this is only one example where the transition occurs with a graded composition. The interfacial region can be considered terminated when no or little additional change in composition occurs upon further processing of the stack. Additionally, the transition actually ends where the composition has a sufficient amount of nickel tungsten oxide such that the material no longer serves at least some of the functions that a dissimilar IC layer could. Undoubtedly, the composition (as distinguished) closer to the CE layer, where the composition is 80% nickel tungsten oxide, functions as the CE layer. Likewise, the composition closer to the interfacial region of the EC layer, in which lithium tungstate is a substantial component, acts as an ionically conductive electrically insulating material. Figure 2C depicts the electrochromic stack of the present invention, where both the EC material and the CE material are important components serving as the interfacial region of the IC layer. Referring to FIG. 2C , starting from the origin and moving from left to right along the x -axis, one can see that a portion of the EC material WO ₃ , which is essentially all tungsten oxide, acts as the EC layer. There is a transition into the interfacial region where there is progressively less tungsten oxide and correspondingly more lithium tungstate. In this example, there is also an increased amount of nickel-tungsten oxide counter electrode material approximately one-third of the way through the portion of the zone that divides into the interfacial region. At approximately midway through the portion divided into the interfacial region, there are approximately 10% each of tungsten oxide and nickel tungsten oxide and 80% lithium tungstate. In this example, there is no abrupt transition between the EC layer and the IC layer or between the IC layer and the CE layer, but rather an interfacial region with a continuous graded composition of both CE material and EC material. In this example, the lithium tungstate component peaks about halfway through the interfacial region, and thus, this region is likely to be the most electrically insulating portion of the interfacial region. As mentioned in [Summary of the Invention] above, the EC layer and the CE layer may include material components that impart a certain resistivity to the EC layer and the CE layer; Lithium tungstate of the three regions is one example of such a material that imparts resistivity to the EC and CE layers. Figures 2A-2C represent only three non-limiting examples of graded compositions serving as interfacial regions of the IC layer in electrochromic devices of the present invention. Those of ordinary skill in the art will appreciate that many variations are possible without departing from the scope of the invention. In each of the examples in Figures 2A-2C, there is at least one layer in which there are only two material components and one of those components is a minimum. The present invention is not limited in this way. Accordingly, one embodiment of the invention is an electrochromic device comprising an electrochromic layer, an interfacial region serving as an IC layer, and a counter electrode layer, wherein each of the aforementioned two layers and one region of the device At least one material component thereof is present in each of the electrochromic layer, the interfacial region, and the counter electrode layer in an amount of at least about 25% by weight, and in another embodiment, at least about 15% by weight. % by weight, in another embodiment, at least about 10% by weight, in another embodiment, at least about 5% by weight, in yet another embodiment, at least about 2% by weight. The amount of electrochromic material and/or counter electrode material in the interface region can be significant, in one embodiment, as much as 50% by weight of the interface region. In many embodiments, however, the ionically conductive electrically insulating material is typically the majority component, while the remainder of the interfacial region is the electrochromic material and/or the counter electrode material. In one embodiment, the interfacial region includes between about 60% and about 95% by weight ionically conductive electrically insulating material, while the remainder of the interfacial region is electrochromic material and/or counter electrode material. In one embodiment, the interfacial region includes between about 70% and about 95% by weight ionically conductive electrically insulating material, while the remainder of the interfacial region is electrochromic material and/or counter electrode material. In one embodiment, the interfacial region includes between about 80% and about 95% by weight ionically conductive electrically insulating material, while the remainder of the interfacial region is electrochromic material and/or counter electrode material. In some embodiments, the interfacial regions in the devices described herein may be relatively distinct, that is, there are relatively distinguishable boundaries at adjacent layers when analyzed, for example, by microscopy, even if the interfacial region contains The same is true for a certain amount of electrochromic material and/or counter electrode material. In these embodiments, the thickness of the interface region can be measured. In embodiments where the interface region is formed by an oxygen-rich (superstoichiometric) region of the EC layer and/or CE layer, the ratio of the thickness of the interface region to the layer or layers forming the interface region is used to characterize the interface A measure of the area. For example, an electrochromic layer is deposited with an oxygen-rich upper layer. The EC layer may comprise a single metal oxide or two or more metal oxides mixed homogeneously or heterogeneously in the layer or more diffusion regions. The EC layer is 550 nm thick and includes an oxygen-rich layer (or region). If about 150 nm of the EC layer is converted to the interfacial region, then about 27% of the EC is converted to the interfacial region, ie, 150 nm divided by 550 nm. In another example, the EC layer includes a first metal oxide region (or layer) and an oxygen-enriched second metal oxide layer (or region). If all or a portion of the oxygen-rich metal oxide layer is converted into an interfacial region, the thickness of the interfacial region divided by the total thickness of the first metal oxide layer and the second metal oxide layer (before forming the interfacial region) is Measurement of interface area. In one embodiment, the interfacial region comprises between about 0.5% and about 50% by thickness of precursor regions (EC and/or CE, including oxygen-enriched portions) used to form the interfacial region, in another embodiment Between about 1% and about 30%, in yet another embodiment between about 2% and about 10%, and in another embodiment between about 3% and about 7%. The inventors have discovered that there are a number of benefits to a graded composition acting as an IC layer. While not wishing to be bound by theory, it is believed that by having such graded regions, the efficiency of the electrochromic transition is greatly improved. There are other benefits, as will be described in more detail below. While not wishing to be bound by theory, it is believed that one or more of the following mechanisms may effect the conversion of EC and/or CE materials to IC functional materials in the interfacial region. However, the implementation or application of the invention is not limited to any of these mechanisms. Each of these mechanisms is consistent with a process that never deposits IC layer material during fabrication of the stack. As is clear elsewhere herein, devices of the present invention need not have separate targets comprising materials for the IC layers. In the first mechanism, direct lithiation of the electrochromic material or the counter electrode material results in IC material (eg, lithium tungstate) in the interfacial region. As will be explained more fully below, various embodiments use direct lithiation of one of the active layers at some point in the fabrication process between the formation of the EC and CE layers. This operation involves exposure of the EC layer or the CE layer (whichever is formed first) to lithium. According to this mechanism, the flux of lithium through the EC or CE layer creates ion-conducting electron-resistant materials, such as lithium salts. Heat or other energy can be applied to drive this flux of lithium. This described mechanism converts the top or exposed portion of the first formed layer (EC or CE layer) before forming the second layer (CE or EC layer). In the second mechanism, lithium diffusing from one of EC or CE to the other layer results in EC and/or Part of one of the CEs is converted at its interface to an interface region with IC functional material. The lithium diffusion can occur after the entire second layer has been formed or after only a portion of the second layer has been formed. Furthermore, diffusion of lithium and subsequent conversion to IC functional material takes place in the first or the second deposited layer and in the EC or CE layer. In one example, an EC layer is formed first, and then the EC layer is lithiated. When the CE layer is subsequently deposited over the EC layer, some lithium diffuses from the underlying EC layer toward and/or into the CE layer, resulting in conversion to an interfacial region containing the IC functional material. In another example, the EC layer is formed first (optionally with an oxygen-rich upper region), then the CE layer is formed and lithiated. Subsequently, some of the lithium from the CE layer diffuses into the EC layer where it forms an interfacial region with IC functional material. In yet another example, an EC layer is deposited first, and then the EC layer is lithiated to produce an IC functional material according to the first mechanism described above. Then, when the CE layer is formed, some lithium diffuses from the underlying EC layer towards the CE layer to create some IC material in the interface region of the CE layer. In this way, the IC functional material resides nominally in both the CE layer and the EC layer next to the interface of the CE layer and the EC layer. In a third mechanism, the EC and CE layers are formed to completion (or at least to the point where the second formed layer is partially completed). Next, the device structure is heated, and the heating converts at least some of the material in the interfacial region into an IC functional material (eg, a lithium salt). Heating (eg, as part of multi-step thermochemical conditioning (MTCC) described further herein) can be performed during deposition or after deposition is complete. In one embodiment, heating is performed after forming the transparent conductive oxide on the stack. In another embodiment, heating is applied after the second layer is partially or fully completed, but before the transparent conductive oxide is applied to the second layer. In some cases, heating is directly and primarily responsible for the transformation. In other cases, heating primarily promotes the diffusion or flow of lithium ions, which creates regions of IC functional material as described in this second mechanism. Finally, in a fourth mechanism, current flowing between the EC layer and the CE layer drives conversion of at least one of the electrochromic material and the counter electrode material into an IC functional material in the interface region. This conversion may occur because, for example, the ion flux associated with the flowing current is so large that it drives the chemical conversion of the EC and/or CE material to the IC material in the interface region. For example, as will be explained below, a large flux of lithium through tungsten oxide in the EC layer can produce lithium tungstate, which acts as an IC material. A lithium flux can be introduced, for example, during the initial activation cycle of a newly formed device. However, this need not be the case, as other opportunities for driving high ion flux may be more appropriate to achieve this conversion. The methods of the present invention can be performed by those of ordinary skill in the art without employing any one or more of the above mechanisms. FIG. 3A is a process flow 300 of the method according to the present invention. In particular, see 305, an EC layer is deposited (on eg the CL of the TCO). Next, see 310, a CE layer is deposited. After depositing the EC and CE layers, then, see 315, an interface region is formed between the EC and CE layers to serve as the IC layer. One embodiment of the present invention is a similar method (not depicted) in which steps 305 and 310 are reversed. The gist of the method is that the interfacial region that acts as the IC layer is formed after the EC and CE layers (in some embodiments, the interfacial region is formed using at least part of one of the EC and CE layers). For this reason, the interfacial region formed in this way is sometimes referred to as the "intrinsic" IC layer. In other embodiments, a dissimilar layer is formed between the EC layer and the CE layer, such as using an EC material or an oxygen-enriched version of the CE material, wherein the layer is again fully or partially converted into an interfacial region after forming the EC and CE layers . Various methods for forming the interface region after forming the EC-CE stack will be described below. Thus, as mentioned, one aspect of the invention is a method of manufacturing an electrochromic device, the method comprising: forming an electrochromic layer comprising an electrochromic material; forming an opposing layer in contact with the electrochromic layer. An electrode layer without first providing an ion-conducting electrically insulating layer between the electrochromic layer and the counter electrode layer, wherein the counter electrode layer includes a counter electrode material; and between the electrochromic layer and the counter electrode layer An interfacial region is formed between the electrode layers, wherein the interfacial region is substantially ionically conductive and substantially electrically insulating. The interfacial region may contain constituent materials of the EC layer, the CE layer, or both. As will be described in more detail below, this interfacial region can be formed in a number of ways. 3B is a graph showing the process flow according to the method described with respect to FIG. 3A (in particular, the process flow for depositing an EC layer, then depositing a CE layer, and finally forming an interfacial region between these layers that acts as an IC layer). Program flow 320 . More specifically, in this example, the EC layer comprises WO3 with various amounts of oxygen (compositions and configurations in particular) _; the CE layer comprises _NiWO , the interfacial region comprises _Li2WO4 , and the TCO materials of indium tin and fluorinated tin oxide. It should be noted that the layers of the electrochromic device will be described below with respect to solid state materials. Solid state materials are desirable due to reliability, consistent properties and process parameters and device performance. Exemplary solid-state electrochromic devices, methods, and apparatus for making them, as well as methods of making electrochromic windows with such devices, are described in Kozlowski et al., U.S. Nonprovisional Patent Application entitled "Fabrication of Low Defectivity Electrochromic Devices" Ser. No. 12/645,111 and U.S. Nonprovisional Patent Application No. 12/645,159 to Wang et al., entitled "Electrochromic Devices," which are hereby incorporated by reference for all purposes. In particular embodiments, the electrochromic devices of the present invention are all solid state and are fabricated in equipment that allows deposition of one or more layers of the stack in a controlled ambient environment. That is, in equipment where the layers are deposited without leaving the equipment and, for example, without breaking the vacuum between deposition steps, thereby reducing contamination and ultimately improving device performance. In certain embodiments, the apparatus of the present invention does not require a separate target for depositing the IC layer as is required in conventional apparatus. As will be appreciated by those of ordinary skill in the art, the present invention is not limited to these materials and methods, however, in certain embodiments, the materials making up the electrochromic stack and the precursor stack (as described below) are all inorganic, Solid (ie, being in a solid state) or inorganic and solid. Because organic materials tend to degrade over time, such as when exposed to ultraviolet light and heat associated with window applications, inorganic materials offer the advantage of reliable electrochromic stacks that can operate for long periods of time. Solid materials also offer the advantage of not having the contamination and leakage problems that liquid materials often have. It should be understood that any one or more of the layers in the stack may contain some amount of organic material, but in many implementations one or more of the layers contain little or no organic material. The same may be true for liquids that may be present in one or more layers in small amounts. It should also be understood that solid state materials may be deposited or otherwise formed by processes using liquid components, such as certain processes using sol-gel or chemical vapor deposition. Referring again to Figure 3B, see 325, the EC layer of WO ₃ is deposited first. 4A-4C are schematic cross-sections depicting formation of electrochromic devices according to particular methods and apparatus of the present invention, and in particular according to program flow 320 . In particular, Figures 4A-4C are used to show three non-limiting examples of how an EC layer comprising WO ₃ can be formed as part of a stack where the interfacial region serving as the IC layer is formed after deposition of the other layers of the stack . In each of Figures 4A-4C, the substrate 402, first TCO layer 404, CE layer 410, and second TCO layer 412 are substantially identical. Also, in each of the three embodiments, a stack is formed without an IC layer, and then the stack is further processed to form an interfacial region within the stack that acts as an IC layer, between the EC layer and the CE layer . Referring to each of Figures 4A-4C, hierarchical structures 400, 403, and 409, respectively, are depicted. Each of these layered structures includes a substrate 402 that is, for example, glass. Any material having suitable optical, electrical, thermal and mechanical properties can be used as the substrate 402 . Such substrates include, for example, glass, plastic, and mirror materials. Suitable plastic substrates include, for example, acrylic, polystyrene, polycarbonate, allyldiethylene glycol carbonate, SAN (styrene acrylonitrile copolymer), poly(4-methyl-1- pentene), polyester, polyamide, etc., and preferably, the plastic should be able to withstand high temperature processing conditions. If a plastic substrate is used, it is preferably hardcoated with, for example, a diamond-like protective coating, a silica/polysiloxane abrasion resistant coating, or the like, such as coatings well known in the art of plastic glazing layer for barrier protection and wear protection. Suitable glasses include clear or colored soda lime glass, including soda lime float glass. Glass can be tempered or untempered. In some embodiments, commercially available substrates such as glass substrates contain transparent conductive layer coatings. Examples of such glasses include conductive-coated glass sold under the trademarks TEC Glass™ (Pilkington of Toledo, Ohio) and SUNGATE™ 300 and SUNGATE™ 500 (PPG Industries of Pittsburgh, Pennsylvania). TEC Glass™ is glass coated with a conductive layer of fluorinated tin oxide. In some embodiments, the optical transmittance (ie, the ratio of transmitted radiation or spectrum to incident radiation or spectrum) of substrate 402 is about 90% to 95%, eg, about 90% to 92%. The substrate can be of any thickness as long as it has suitable mechanical properties to support the electrochromic device. While substrate 402 may be of any size, in some embodiments it is about 0.01 mm to 10 mm thick, preferably about 3 mm to 9 mm thick. In some embodiments of the invention, the substrate is architectural glass. Architectural glass is glass used as a building material. Architectural glass is commonly used in commercial buildings, but can also be used in residential buildings, and often (but not necessarily) separates the indoor environment from the outdoor environment. In certain embodiments, the architectural glass is at least 20 inches by 20 inches, and may be larger, for example, up to about 72 inches by 120 inches. Architectural glass is typically at least about 2 mm thick. Architectural glass less than about 3.2 mm thick cannot be tempered. In some embodiments of the invention with architectural glass as the substrate, the substrate can be tempered even after the electrochromic stack has been fabricated on the substrate. In some embodiments where architectural glass is used as the substrate, the substrate is soda lime glass from a tin float line. The percent transmission over the visible spectrum (ie, the overall transmission across the visible spectrum) of architectural glass substrates is typically 80% greater than that of neutral substrates, but it may be lower than that of colored substrates. Preferably, the substrate has a percent transmission over the visible spectrum of at least about 90% (eg, about 90% to 92%). The visible spectrum is the spectrum to which the typical human eye responds, generally from about 380 nm (purple) to about 780 nm (red). In some cases, the glass has a surface roughness between about 10 nm and about 30 nm. In one embodiment, the substrate 402 is a sodium glass with a sodium diffusion barrier (not shown) to prevent the diffusion of sodium ions into the electrochromic device. For purposes of this description, this configuration is referred to as "substrate 402." Referring again to layered structures 400 , 403 , and 409 , a first TCO layer 404 , for example made of fluorinated tin oxide or other suitable material that is conductive and transparent, is deposited over substrate 402 . Transparent conductive oxides include metal oxides and metal oxides doped with one or more metals. Examples of such metal oxides and doped metal oxides include indium oxide, indium tin oxide, doped indium oxide, tin oxide, doped tin oxide, zinc oxide, aluminum zinc oxide, doped Zinc oxide, ruthenium oxide, doped ruthenium oxide and the like. In one embodiment, the second TCO layer has a thickness between about 20 nm and about 1200 nm, in another embodiment between about 100 nm and about 600 nm, in another embodiment, about 350 nm nm thick. The TCO layers should have a suitable sheet resistance ( _Rs ) due to the relatively large area spanned by the layers. In some embodiments, the sheet resistance of the TCO layer is between about 5 ohms and about 30 ohms per square. In some embodiments, the sheet resistance of the TCO layer is about 15 ohms per square. In general, it is desired that the sheet resistance of each of the two conductive layers be approximately the same. In one embodiment, the two layers (eg, 404 and 412 ) each have a sheet resistance of about 10-15 ohms per square. Each of the layered structures 400, 403, and 409 includes a stack 414a, 414b, and 414c, respectively, each of which includes a first TCO layer 404, a CE layer 410, and a second TCO layer over a substrate 402. Layer 412. Each of the layered structures 400, 403 and 409 differs in how the EC layer system is formed, which in each case affects the morphology of the resulting interfacial region. Consistent with process flow 320 of FIG. 3B , each of stacks 414 a , 414 b , and 414 c includes an electrochromic layer deposited over first TCO layer 404 . The electrochromic layer can contain any one or more of a number of different electrochromic materials including metal oxides. Such metal oxides include tungsten oxide (WO ₃ ), molybdenum oxide (MoO ₃ ), niobium oxide (Nb ₂ O ₅ ), titanium oxide (TiO ₂ ), copper oxide (CuO), iridium oxide (Ir ₂ O ₃ ) , chromium oxide (Cr ₂ O ₃ ), manganese oxide (Mn ₂ O ₃ ), vanadium oxide (V ₂ O ₅ ), nickel oxide (Ni ₂ O ₃ ), cobalt oxide (Co ₂ O ₃ ), and the like. In some embodiments, the metal oxide is doped with one or more dopants, such as lithium, sodium, potassium, molybdenum, niobium, vanadium, titanium, and/or other suitable metals or metal-containing compounds. Mixed oxides (eg, W-Mo oxide, WV oxide) may also be used in certain embodiments, ie, the electrochromic layer includes two or more of the aforementioned metal oxides. An electrochromic layer comprising a metal oxide is capable of receiving ions transferred from a counter electrode layer. In some embodiments, tungsten oxide or doped tungsten oxide is used for the electrochromic layer. In one embodiment of the invention, the electrochromic layer is made essentially of WOx, where "x _" refers to the atomic ratio of oxygen to tungsten in the electrochromic layer, and x is between about 2.7 and 3.5. It has been suggested that only substoichiometric tungsten oxide exhibits electrochromism; that is, stoichiometric tungsten oxide (WO ₃ ) does not exhibit electrochromism. In a more particular embodiment, WO _x , where x is less than 3.0 and is at least about 2.7, is used for the electrochromic layer. In another embodiment, the electrochromic layer is WO _x , where x is between about 2.7 and about 2.9. Techniques such as Rutherford Backscattering Spectroscopy (RBS) can identify the total number of oxygen atoms including oxygen atoms bonded to tungsten and oxygen atoms not bonded to tungsten. In some instances, tungsten oxide layers (where x is 3 or greater) exhibit electrochromism, possibly due to unbound excess oxygen and substoichiometric tungsten oxide. In another embodiment, the tungsten oxide layer has a stoichiometric amount of oxygen or more, where x is from 3.0 to about 3.5. In some embodiments of the invention, at least a portion of the EC layer has an excess of oxygen. This more highly oxidized region of the EC layer is used as a precursor to form the ion-conducting electrically insulating region that acts as the IC layer. In other embodiments, a dissimilar layer of highly oxidized EC material is formed between the EC layer and the CE layer for eventual conversion at least partially to an ion-conducting electrically insulating interfacial region. In particular embodiments, the tungsten oxide is crystalline, nanocrystalline or amorphous. In some embodiments, tungsten oxide is substantially nanocrystalline and has an average grain size of about 5 nm to 50 nm (or about 5 nm to 20 nm), as characterized by transmission electron microscopy (TEM) . Tungsten oxide morphology or microstructure can also be characterized as nanocrystalline using x-ray diffraction (XRD) and/or electron diffraction such as selected area electron diffraction (SAED). For example, nanocrystalline electrochromic tungsten oxide may be characterized by the following XRD characteristics: a crystal size of about 10 to 100 nm (eg, about 55 nm). In addition, nanocrystalline tungsten oxide can exhibit limited long-range order, eg, about a few (about 5 to 20) tungsten oxide unit cells. Therefore, for convenience, the remainder of the process flow 320 in FIG. 3B will be further described with respect to the first embodiment, including the formation of the EC layer 406 shown in FIG. 4A. Next, the second and third embodiments respectively represented in FIGS. 4B and 4C will be described below, with particular emphasis on the formation and morphology and/or microstructure of their respective EC layers. As mentioned with reference to Figure 3B, see 325, an EC layer is deposited. In a first embodiment (shown in FIG. 4A ), a substantially homogeneous EC layer 406 (comprising WO ₃ ) is formed as part of stack 414 a , wherein the EC layer is in direct contact with CE layer 410 . _In one embodiment, the EC layer comprises WO3, as described above. In one embodiment, heating is applied during at least a portion of the deposition of WO ₃ . In a particular embodiment, several passes are made through the sputtering target, with a portion _of the WO3 being deposited on each pass, and after each pass, heat is applied to, for example, the substrate 402 to deposit a layer of WO3 _on the deposited layer 406. Adjust _WO3 before the next section. In other embodiments, the WO ₃ layer can be continuously heated during deposition, and the deposition can be done in a continuous fashion rather than several passes over the sputtering target. In one embodiment, the thickness of the EC layer is between about 300 nm and about 600 nm. As mentioned, the thickness of the EC layer depends on the desired result and the method of forming the IC layer. In the embodiment described with respect to FIG. 4A , the EC layer is between about 500 nm and about 600 nm thick using a tungsten target and includes between about 40% and about 80% O and about ₂₀ % and about A sputtering gas of between 60% Ar sputters WO ₃ , and the substrate in which WO ₃ is deposited is at least intermittently heated to between about 150° C. and about 450° C. during the formation of the EC layer. _In a specific embodiment, the EC layer is about 550 nm thick WO3 sputtered using a tungsten target, wherein the sputtering gas includes about 50% to about 60% _O2 and about 40% to about 50% O2 Ar, and the substrate deposited with WO ₃ is at least intermittently heated to between about 250° C. and about 350° C. during the formation of the electrochromic layer. In these examples, the WO ₃ layer is substantially homogeneous. In one embodiment, WO ₃ is substantially polycrystalline. It is believed that heating WO ₃ at least intermittently during deposition aids in the formation of polycrystalline forms of WO ₃ . As mentioned, many materials are suitable for the EC layer. In general, in electrochromic materials, the coloring (or any optical property, such as a change in absorbance, reflectivity, and transmittance) of an electrochromic material is achieved by reversible ion intercalation (e.g., intercalation) into the material. ) and the corresponding injection of charge-balancing electrons. Typically, a certain fraction of the ions responsible for the optical transition are irreversibly bound together in the electrochromic material. As described herein, some or all of the irreversibly bound ions serve to compensate for a "blind charge" in the material. In most electrochromic materials, suitable ions include lithium ions (Li ⁺ ) and hydrogen ions (H ⁺ ) (ie, protons). However, in some cases other ions will be suitable. Such ions include, for example, deuterium ions (D ⁺ ), sodium ions (Na ⁺ ), potassium ions (K ⁺ ), calcium ions (Ca ⁺⁺ ), barium ions (Ba ⁺⁺ ), strontium ions (Sr ⁺⁺ ) and magnesium ions (Mg ⁺⁺ ). In various embodiments described herein, lithium ions are used to generate electrochromism. The intercalation of lithium ions into tungsten oxide (WO _3-y (0<y≤~0.3)) changes tungsten oxide from transparent (discolored state) to blue (colored state). In a typical process where the EC layer comprises or is tungsten oxide, lithium is deposited on the EC layer 406, for example by sputtering, to satisfy blind charging (discussed in more detail below with reference to FIGS. 6 and 7), see FIG. 3B 330 of the program flow. In one embodiment, lithiation is performed in an integrated deposition system in which the vacuum is not broken between deposition steps. It should be noted that in some embodiments lithium is not added at this stage, but can be added after the counter electrode layer is deposited, or in other embodiments lithium is added after the TCO is deposited. Referring again to FIG. 4A , next, a CE layer 410 is deposited on the EC layer 406 . In some embodiments, the counter electrode layer 410 is inorganic and/or solid. The counter electrode layer may comprise one or more of a number of different materials capable of acting as a reservoir for ions when the electrochromic device is in a faded state. During an electrochromic transition initiated by, for example, application of an appropriate potential, the counter electrode layer transfers some or all of the ions it holds to the electrochromic layer, causing the electrochromic layer to change to a colored state. Meanwhile, in the case of NiO and/or NiWO, the counter electrode layer is colored due to loss of ions. In some embodiments, suitable materials for the counter electrode include nickel oxide (NiO), nickel tungsten oxide (NiWO), nickel vanadium oxide, nickel chromium oxide, nickel aluminum oxide, nickel manganese oxide, nickel magnesium oxide, chromium oxide (Cr ₂ O ₃ ), manganese oxide (MnO ₂ ) and Prussian blue. Optical passive counter electrodes include cerium titanium oxide (CeO ₂ -TiO ₂ ), cerium zirconium oxide (CeO ₂ -ZrO ₂ ), nickel oxide (NiO), nickel tungsten oxide (NiWO), vanadium oxide (V ₂ O ₅ ) and A mixture of oxides (for example, a mixture of Ni ₂ O ₃ and WO ₃ ). Doped formulations of these oxides may also be used, where dopants include, for example, tantalum and tungsten. Since the counter electrode layer 410 contains ions for producing the electrochromic phenomenon in the electrochromic material when the electrochromic material is in a faded state, the counter electrode preferably has a high Transmittance and neutral color. The shape of the counter electrode can be crystalline, nanocrystalline or amorphous. In some embodiments, where the counter electrode layer is nickel tungsten oxide, the counter electrode material is amorphous or substantially amorphous. Such substantially amorphous nickel tungsten oxide counter electrodes have been found to perform better under certain conditions than their crystalline counterparts. As described below, the amorphous state of nickel tungsten oxide can be obtained by using specific processing conditions. While not wishing to be bound by any theory or mechanism, it is believed that amorphous nickel-tungsten oxide is produced by relatively high energy atoms in the sputtering process. Higher energy atoms are obtained, for example, in sputtering processes with higher target power, lower chamber pressure (ie, higher vacuum), and smaller source-to-substrate distance. Under the described processing conditions, higher density films with better stability under UV/heat exposure were produced. In certain embodiments, the amount of nickel present in the nickel tungsten oxide may be up to about 90% by weight of the nickel tungsten oxide. In a specific embodiment, the mass ratio of nickel to tungsten in the nickel tungsten oxide is between about 4:6 and 6:4, and in one example is about 1:1. In one embodiment, NiWO includes between about 15 atomic percent and about 60 percent Ni, and between about 10 percent and about 40 percent W. In another embodiment, NiWO comprises between about 30 atomic percent and about 45 percent Ni, and between about 15 percent and about 35 percent W. In another embodiment, NiWO comprises between about 30 atomic percent and about 45 percent Ni, and between about 20 percent and about 30 percent W. In one embodiment, NiWO includes about 42 atomic percent Ni and about 14 percent W. In one embodiment, as described above, see 335 of FIG. 3B , the CE layer 410 is NiWO. In one embodiment, the thickness of the CE layer is between about 150 nm and about 300 nm, in another embodiment between about 200 nm and about 250 nm, in another embodiment about 230 nm. In a typical process, lithium is also applied to the CE layer until the color of the CE layer fades. It should be understood that reference to transitions between colored and faded states is non-limiting and implies only one example of many possible electrochromic transitions that may be implemented. Unless otherwise stated herein, whenever a fade-to-color transition is mentioned, the corresponding device or process encompasses other optical state transitions such as non-reflective-reflective, transparent-opaque, and the like. In addition, the term "faded" refers to an optically neutral state, such as uncolored, transparent or translucent. Still further, unless otherwise stated herein, the "color" of an electrochromic transition is not limited to any particular wavelength or range of wavelengths. As is generally understood by those skilled in the art, selection of appropriate electrochromic materials and counter electrode materials governs the associated optical transition. In a particular embodiment, see 340 of FIG. 3B , lithium is added (eg, via sputtering) to the NiWO CE layer. In a particular embodiment, see 345 of FIG. 3B , an additional amount of lithium is added after enough lithium has been introduced to completely decolorize the NiWO (this procedure is optional, and in one embodiment, is not used at this stage of the procedure. Add excess lithium). In one embodiment, the additional amount is between about 5% and about 15% excess based on the amount needed to discolor the counter electrode layer. In another embodiment, the excess lithium added to the CE layer is about a 10% excess based on the amount needed to discolor the counter electrode layer. After depositing the CE layer 410, decolorizing it with lithium, and adding additional lithium, see 350 of FIG. 3B, a second TCO layer 412 is deposited over the counter electrode layer. In one embodiment, the transparent conductive oxide includes indium tin oxide, and in another embodiment, the TCO layer is indium tin oxide. In one embodiment, the thickness of this second TCO layer is between about 20 nm and about 1200 nm, in another embodiment between about 100 nm and about 600 nm, in another embodiment about 350 nm nm. Referring again to FIG. 4A, once layered structure 400 is complete, it is subjected to thermochemical conditioning that converts at least a portion of stack 414a into an IC layer (if it has not been converted due to lithium diffusion or other mechanisms). Stack 414a is a precursor and not an electrochromic device because it does not yet have an ionically conductive/electrically insulating layer (or region) between EC layer 406 and CE layer 410 . In this particular embodiment, a portion of the EC layer 406 is converted to an IC layer 408 to form a functional electrochromic device 401 in a two-step process. Referring to Figure 3B, see 355, the layered structure 400 is subject to MTCC. In one embodiment, the stack is first subjected to heating at between about 150° C. and about 450° C. for between about ₁₀ minutes and about 30 minutes under an inert atmosphere (eg, argon), and then heated under O for Between about 1 minute and about 15 minutes. In another embodiment, the stack is heated at about 250° C. under an inert atmosphere for about 15 minutes, and then heated under O ₂ for about 5 minutes. Next, layered structure 400 is subjected to heating in air. In one embodiment, the stack is heated in air at between about 250° C. and about 350° C. for between about 20 minutes and about 40 minutes. In another embodiment, the stack is heated in air at about 300° C. Heating took about 30 minutes. The energy required to implement MTCC need not be radiant heat energy. For example, in one embodiment, MTCC is implemented using ultraviolet radiation. Other energy sources may also be used without departing from the scope of the present invention. After the multi-step thermochemical conditioning, program flow 320 is complete and a functional electrochromic device is established. As mentioned, and while not wishing to be bound by theory, it is believed that the lithium in stack 414a combines with a portion of EC layer 406 and/or CE layer 410 to form interfacial region 408 which acts as an IC layer. It is believed that the interface region 408 is mainly lithium tungstate (Li ₂ WO ₄ ), which is known to have good ion-conducting and electrical-insulating properties compared to conventional IC layer materials. As discussed above, it is not clearly known how this phenomenon occurs. There are chemical reactions that must occur during the multi-step thermochemical conditioning to form the ion-conducting electrically insulating region 408 between the EC layer and the CE layer, but it is also believed that the initial flux of lithium traveling through the stack (e.g., by The excess lithium added to the CE layer (provided) plays a role in the formation of the IC layer 408 . The thickness of the ion-conducting electrically insulating region can vary depending on the materials used and the processing conditions used to form the layer. In some embodiments, the interfacial region 408 has a thickness between about 10 nm and about 150 nm, in another embodiment between about 20 nm and about 100 nm, and in other embodiments between about 30 nm and about 100 nm. between about 50 nm. As mentioned above, there are many suitable materials for forming the EC layer. Thus, using, for example, lithium or other suitable ions in the above method, one can make other interfacial regions that serve as IC layers starting from oxygen-enriched EC materials. Suitable EC materials for this purpose include, but are not limited to, _SiO2 , _Nb2O5 , _Ta2O5 , _TiO2 , _{ZrO2 ,} and _{CeO2 .} In particular embodiments using lithium ions, ion-conducting materials such as, but not limited to, lithium silicate, lithium aluminum silicate, lithium aluminum borate, lithium aluminum fluoride, lithium borate, lithium nitride, lithium zirconium silicate, Lithium niobate, lithium borosilicate, lithium phosphosilicate, and other such lithium-based ceramic materials, silica or silicon oxide (including lithium silicon oxide) can be made to act as the interfacial region of the IC layer. As mentioned, in one embodiment, the precursor to the ion-conducting region is an oxygen-rich (superstoichiometric) layer converted to an ion-conducting/electrically insulating region via lithiation and MTCC as described herein. While not wishing to be bound by theory, it is believed that after lithiation, excess oxygen forms lithium oxide, which further forms lithium salts (i.e., lithium electrolytes), such as lithium tungstate ( _{Li2WO4 )} , lithium molybdate (Li ₂ MoO ₄ ), lithium niobate (LiNbO ₃ ), lithium tantalate (LiTaO ₃ ), lithium titanate (Li ₂ TiO ₃ ), lithium zirconate (Li ₂ ZrO ₃ ), and the like. In one embodiment, the interface region includes at least one of the following: tungsten oxide (WO _3+x , 0≤x≤1.5), molybdenum oxide (MoO _3+x , 0≤x≤1.5), niobium oxide (Nb ₂ O _5+x , 0≤x≤2), titanium oxide (TiO _2+x , 0≤x≤1.5), tantalum oxide (Ta ₂ O _5+x , 0≤x≤2), zirconia ( ZrO _2+x , 0≤x≤1.5) and cerium oxide (CeO _2+x , 0≤x≤1.5). However, any material can be used for the ion-conducting interfacial region as long as the material can be fabricated to have a low degree of defectivity and it allows the passage of ions between the counter electrode layer 410 and the electrochromic layer 406 while substantially preventing the passage of electrons. Can. The material can be characterized as substantially conducting ions and substantially resisting electrons. In one embodiment, the ionic conductor material has an ionic conductivity between about 10 ⁻¹⁰ Siemens/cm (or ohm ⁻¹ cm ⁻¹ ) and about 10 ⁻³ Siemens/cm and greater than 10 ⁵ ohm-cm resistivity. In another embodiment, the ionic conductor material has an ionic conductivity between about 10 ⁻⁸ Siemens/cm and about 10 ⁻³ Siemens/cm and a resistivity greater than 10 ¹⁰ ohm-cm. While ionically conducting layers should be substantially resistant to leakage current (e.g., providing a leakage current of no greater ^than about 15 μA/cm), it has been found that some devices fabricated as described herein have surprisingly high leakage currents (e.g., , between about 40 μA/cm and about 150 μA/cm), yet still provide good color variation across the device and operate efficiently. As mentioned above, there are at least two other ways of creating an ionically conductive electrically insulating region between the EC layer and the CE layer after forming the stack. These additional embodiments will be described below with reference to the specific example of using tungsten oxide for the IC layer. Also, as mentioned above, interfacial regions with IC properties can be formed in situ during fabrication of the stack when, for example, lithium diffusion or heat converts some of the EC and/or CE layers into interfacial regions. In general, there are particular benefits to establishing ion-conducting regions later in the process. First, the ion-conducting material can be protected from some of the harsh processing that occurs during deposition and lithiation of the EC and CE layers. For example, depositing these layers by a plasma process is often accompanied by a large voltage drop immediately after the stack, often in the order of 15-20 volts. These large voltages can damage or cause decomposition of sensitive ion-conducting materials. By moving IC material formation to a later stage in the process, the material is not exposed to potentially damaging voltage extremes. Second, by forming the IC material later in the process, we can better control some processing conditions that were not possible before completing both the EC and CE layers. These conditions include lithium diffusion and current flow between the electrodes. Controlling these and other conditions late in the process provides additional flexibility in tailoring the physical and chemical properties of IC materials to specific applications. Thus, not all of the benefits of the present invention are due to the unique interfacial region serving as the IC layer, ie, there are manufacturing and other benefits as well. It has been observed that ion-conducting materials formed according to some of the embodiments described herein have superior efficacy. For example, it has been found that the device switching speed is very fast (eg, less than 10 minutes, in one example about 8 minutes) to achieve about 80% final state, compared to 20-25 minutes or more for conventional devices. In some examples, the devices described herein have switching speeds that are orders of magnitude better than conventional devices. This may be attributable to a larger amount of lithium disposed in the interfacial region and/or in the graded interface that can be easily transferred (eg, between the EC and the interfacial region and/or between the CE and the interfacial region). Such lithium may be in the EC and/or CE phase intermingled with the IC present in the interfacial region. It may also be due to the relatively thin layer or network of IC material present in the interfacial region. In support of this notion, it has been observed that some devices fabricated according to the teachings herein have high leakage current, yet surprisingly exhibit good color change and good efficiency. In some cases, robustly performing devices have been found to have leakage current densities of at least about 100 μA/cm. Referring now to FIG. 4B, in a second embodiment, the initially deposited EC material of the stack 414b is actually _two layers: a first WO3 layer 406, which is similar to layer 406 in FIG. 4A, but is about 350 nm thick. Between about 450 nm and about 450 nm, the first layer is sputtered using a tungsten target and a first sputtering gas comprising between about 40% and about 80% O and between about ₂₀ % and about 60% Ar and a second WO ₃ layer 405 having a thickness between about 100 nm and about 200 nm, the second layer using a tungsten target and comprising between about 70% and 100% O ₂ and between 0% and about 30% The second sputtering gas sputtering with Ar between %. In this embodiment, heat is applied by at least intermittently heating the substrate 402 to between about 150° C. and about 450° C. during the deposition of the first WO ₃ layer 406 , but during the deposition of the second WO ₃ layer 405 No heating or substantially no heating during the period. In a more particular embodiment, layer 406 is about 400 nm thick, and the first sputtering gas includes between about 50% and about 60% _O2 and between about 40% and about 50% Ar; The second WO ₃ layer 405 is about 150 nm thick, and the second sputtering gas is substantially pure O ₂ . In this embodiment, heat is applied at least intermittently to between about 200° C. and about 350° C. during the formation of the first WO ₃ layer 406 , but no heat or substantially no heat is applied during the formation of the second WO ₃ layer 405 . heating. In this way, the first WO ₃ layer is substantially polycrystalline, while the second WO ₃ layer need not be. Referring again to FIG. 4B, as described above with respect to FIGS. 3B and 4A, the stack is completed by lithiation of EC layers 406 and 405 to substantially or substantially satisfy the blind charge, deposition of CE layer 410, lithiation of CE layer To a faded state, additional lithium is added and a second TCO layer 412 is deposited to complete the layered stack 403 . Similar thermochemical adjustments are performed on layered stack 403 to provide layered stack 407, a functional electrochromic device including ion-conducting electrically insulating region 408a. While not wishing to be bound by theory, in this example it is believed that the oxygen-rich layer 405 of WO ₃ acts primarily as a source of precursor material to form the interfacial region 408a. In this example, the entire oxygen-enriched WO ₃ layer is depicted as converting into interfacial region 408a, however, it has been found that this is not always the case. In some embodiments, only a portion of the oxygen-rich layer is converted to form an interfacial region that functions as an IC layer. Referring now to FIG. 4C, in a third embodiment, layered stack 409 includes EC layer 406a (which has a graded composition of WO ₃ and is formed as part of stack 414c), wherein the graded composition includes varying amounts of oxygen. In a non-limiting example, there is a higher oxygen concentration in the EC layer 406a at the interface of the EC-CE layer (410) than at the interface of the TCO layer 404 and the EC layer 406a. In one embodiment, the EC layer 406a is a graded composition WO ₃ layer sputtered with a tungsten target and a sputtering gas with a thickness between about 500 nm and about 600 nm, wherein the sputtering gas The color changing layer initially comprises between about 40% and about 80% O and between about ₂₀ % and about 60% Ar, and the sputtering gas comprises about 70% and Ar at the end of sputtering the electrochromic layer. Between 100% O and between ₀ % and about 30% Ar, and wherein heat is applied to the substrate 402, for example, to about 150°C and about 450°C at least intermittently during the initiation of the formation of the EC layer 406a In between, but not or substantially not, heat is applied during the deposition of at least a final portion of the EC layer 406a. _In a more specific embodiment, the graded composition WO layer is about 550 nm thick; the sputtering gas comprises between about 50% and about 60% O and 40 _% O at the start of sputtering the electrochromic layer and about 50% Ar, and the sputtering gas is substantially pure O at the end of sputtering the electrochromic layer _; and wherein heat is applied at least intermittently during the beginning of formation of the electrochromic layer to For example, substrate 402 to between about 200°C and about 350°C, but no or substantially no heat is applied during deposition of at least a final portion of the electrochromic layer. In one embodiment, heat is applied at the temperature range at the beginning of the deposition and is tapered to no heat when about half of the EC layer is deposited, while the sputtering gas composition is along the A substantially linear rate is adjusted from between about 50% and about 60% _O2 and between about 40% and about 50% Ar to substantially pure _O2 . More generally, the interfacial region typically (but not necessarily) has a heterostructure comprising at least two discrete components represented by different phases and/or compositions. Additionally, the interfacial region may include a gradient among the two or more discrete components, such as an ion-conducting material and an electrochromic material (eg, a mixture of lithium tungstate and tungsten oxide). The gradient can provide, for example, variable composition, microstructure, resistivity, dopant concentration (eg, oxygen concentration), stoichiometry, density, and/or grain size range. The gradient can have transitions of many different forms, including linear transitions, S-shaped transitions, Gaussian transitions, and the like. In one example, the electrochromic layer includes regions of tungsten oxide transitioning into regions of superstoichiometric tungsten oxide. Part or all of the superstoichiometric oxide region is converted into an interfacial region. In the final structure, the tungsten oxide region is substantially polycrystalline, and the microstructure transitions to substantially amorphous at the interface region. In another example, the electrochromic layer includes regions of tungsten oxide transitioning into regions of (superstoichiometric) niobium oxide. Part or all of the niobium oxide region is converted into an interfacial region. In the final structure, the tungsten oxide region is substantially polycrystalline, and the microstructure transitions to substantially amorphous at the interface region. Referring again to FIG. 4C, as described above with respect to FIGS. 3B and 4A, the stacking is accomplished by: lithiation of the EC layer 406a to substantially or substantially satisfy the blind charge, deposition of the CE layer 410, lithiation of the CE layer to a faded state , adding additional lithium and depositing a second TCO layer 412 to complete the layered stack 409 . A similar multi-step thermochemical conditioning is performed on the layered stack 409 to provide the layered stack 411, comprising at least a portion of the ionically conductive electrically insulating region 408b and the original layered EC layer 406a (which serves as the EC in the functional electrochromic device 411 layer) functional electrochromic device. While not wishing to be bound by theory, in this example it is believed that the uppermost oxygen-rich portion of the graded layer of WO ₃ primarily forms the graded interfacial region 408b. While not wishing to be bound by theory, it is possible that the formation of the interfacial region is self-limiting and depends on the relative amounts of oxygen, lithium, electrochromic material and/or counter electrode material in the stack. In various embodiments described herein, electrochromic stacks are described as having no or substantially no heating during certain processing stages. In one embodiment, after the heating step, the stack is actively or passively (eg, using a heat sink) cooled. The apparatus of the present invention includes active and passive cooling components, for example, active cooling can include platen cooling by fluid circulation, cooling by exposure to cold (eg, via expansion) gas, refrigeration units, and the like. Passively cooled components may include heat sinks, such as metal blocks and the like, or simply remove the substrate from heat exposure. Another aspect of the present invention is a method of manufacturing an electrochromic device, the method comprising: (a) forming an electrochromic layer comprising an electrochromic material or a counter electrode layer comprising a counter electrode material; (b) An intermediate layer is formed over the electrochromic layer or the counter electrode layer, wherein the intermediate layer includes an oxygen-enriched form of at least one of the electrochromic material, the counter electrode material, and an additional material, wherein the additional material comprising a dissimilar electrochromic material or counter electrode material, wherein the intermediate layer is not substantially electrically insulating; (c) forming the other of the electrochromic layer and the counter electrode layer; and (d ) allows at least a portion of the intermediate layer to become substantially electrically insulating. In one embodiment, the electrochromic material is WO ₃ . In another embodiment, (a) includes sputtering WO using a tungsten target and a first sputtering gas comprising between about 40% and about 80% O and between about ₂₀ % and about 60% Ar. ₃ to achieve a thickness between about 350 nm and about 450 nm, and at least intermittently heating to between about 150° C. and about 450° C. during formation of the electrochromic layer. In another embodiment, (b) includes a second sputtering without heating using a tungsten target and including between about 70% and 100% O and between ₀ % and about 30% Ar The WO ₃ is gas sputtered to a thickness between about 100 nm and about 200 nm. In yet another embodiment, the method further comprises sputtering lithium onto the intermediate layer until the blind charge is substantially or substantially satisfied. In one embodiment, the counter electrode layer includes NiWO with a thickness between about 150 nm and about 300 nm. In another embodiment, lithium is sputtered onto the counter electrode layer until the counter electrode layer fades. In another embodiment, an additional amount of lithium is sputtered onto the counter electrode layer between about 5% and about 15% over the amount needed to decolorize the counter electrode layer. In another embodiment, a transparent conductive oxide layer is deposited over the counter electrode layer. In one embodiment, the transparent conductive oxide includes indium tin oxide, and in another embodiment, the transparent conductive oxide is indium tin oxide. In another embodiment, the stack formed according to the above embodiments is heated under Ar at between about 150° C. and about 450° C. for between about 10 minutes and about 30 minutes, and then heated under O for about ₁ minutes and about 15 minutes, and then heated in air at between about 250° C. and about 350° C. for between about 20 minutes and about 40 minutes. In another embodiment, (a) comprises a first electrochromic material of sputtered MO _x , wherein M is a metal or non-metal element, and x indicates the ratio of stoichiometric oxygen to M, and (b) comprises The second electrochromic material of sputtered NO _y is used as an intermediate layer, wherein N is the same or different metal or non-metal element, and y indicates the ratio of superstoichiometric oxygen to N. In one embodiment, M is tungsten and N is tungsten. In another embodiment, M is tungsten, and N is selected from the group consisting of niobium, silicon, tantalum, titanium, zirconium, and cerium. Another embodiment of the present invention is an electrochromic device comprising: (a) an electrochromic layer comprising an electrochromic material; (b) a counter electrode layer comprising a counter electrode material; and (c) an electrochromic layer comprising an electrochromic material; The interface region between the electrochromic layer and the counter electrode layer, wherein the interface region includes an electrically insulating ion-conducting material and at least one of the electrochromic material, the counter electrode material, and an additional material, wherein the Additional materials include dissimilar electrochromic materials or counter electrode materials. In one embodiment, at least one of the electrically insulating ion-conducting material and the electrochromic material, the counter electrode material and the additional material are substantially uniformly distributed within the interface region. In another embodiment, at least one of the electrically insulating ion-conducting material and the electrochromic material, the counter electrode material and the additional material comprises a compositional gradient in a direction perpendicular to the layers. In another embodiment, consistent with any of the two preceding embodiments, the electrically insulating ion-conducting material includes lithium tungstate, the electrochromic material includes tungsten oxide, and the counter electrode material includes nickel tungsten oxide . In a specific implementation of one of the foregoing embodiments, no additional material is present. In one embodiment, the thickness of the electrochromic layer is between about 300 nm and about 500 nm, the thickness of the interface region is between about 10 nm and about 150 nm, and the thickness of the counter electrode layer is about Between 150 nm and about 300 nm. In another embodiment, the thickness of the electrochromic layer is between about 400 nm and about 500 nm; the thickness of the interface region is between about 20 nm and about 100 nm, and the thickness of the counter electrode layer is between Between about 150 nm and about 250 nm. In yet another embodiment, the thickness of the electrochromic layer is between about 400 nm and about 450 nm; the thickness of the interface region is between about 30 nm and about 50 nm, and the thickness of the counter electrode layer is between Between about 200 nm and about 250 nm. Another embodiment is a method of fabricating an electrochromic device, the method comprising: by using a sputtering gas comprising between about 40% and about 80% O and between about ₂₀ % and about 60% Ar sputtering a tungsten target to produce _WO3 to a thickness between about 500 nm and about 600 nm to deposit an electrochromic layer, wherein the substrate _on which the WO3 is deposited is at least intermittently during formation of the electrochromic layer heating to between about 150° C. and about 450° C.; sputtering lithium onto the electrochromic layer until the blind charge is satisfied; depositing a counter electrode layer on the electrochromic layer without first providing an ion-conducting electrically insulating layer between the electrochromic layer and the counter electrode layer, wherein the counter electrode layer comprises NiWO; sputtering lithium onto the counter electrode layer until the counter electrode layer is substantially discolored; And an interfacial region is formed between the electrochromic layer and the counter electrode layer, wherein the interfacial region is substantially ionically conductive and substantially electrically insulating. In one embodiment, forming the interfacial region includes the stack of MTCCs alone or together with substrate, conductive layer and/or encapsulation layer. The electrochromic device of the present invention may include one or more additional layers (not shown) such as one or more passive layers, for example, to improve certain optical properties (provide moisture or scratch resistance) to hermetically seal Sealing the electrochromic device and the like. Typically, but not necessarily, a capping layer is deposited on the electrochromic stack. In some embodiments, the capping layer is SiAlO. In some embodiments, the capping layer is deposited by sputtering. In one embodiment, the thickness of the capping layer is between about 30 nm and about 100 nm. As should be appreciated from the foregoing discussion, the electrochromic devices of the present invention can be sputtered in a single chamber apparatus (e.g., with, for example, tungsten targets, nickel targets, and lithium targets and oxygen and argon sputtering gases. tool) made in. As mentioned, due to the nature of the interfacial region formed to serve the purpose of a conventional dissimilar IC layer, a separate target for sputtering the IC layer is not necessary. It is of particular interest to the inventors, for example, to fabricate electrochromic devices of the present invention in a high-throughput manner, and therefore it is desirable to have equipment that can sequentially fabricate electrochromic devices of the present invention as substrates pass through an integrated deposition system. For example, the inventors are particularly interested in fabricating electrochromic devices on windows, particularly architectural glass flake windows (described above). Accordingly, another aspect of the invention is an apparatus for fabricating an electrochromic device comprising: an integrated deposition system comprising: (i) a first deposition station containing a material source configured to deposit an electrochromic layer of an electrochromic material; and (ii) a second deposition station configured to deposit a counter electrode layer comprising a counter electrode material; The manner of depositing a stack having an intermediate layer sandwiched between the electrochromic layer and the counter electrode layer delivers the substrate through the first deposition station and the second deposition station; wherein the first deposition Either or both of the station and the second deposition station are also configured to deposit the intermediate layer over the electrochromic layer or the counter electrode layer, and wherein the intermediate layer includes the electrochromic material or the counter electrode layer To an oxygen-enriched form of the electrode material, and wherein the first deposition station and the second deposition station are interconnected in series and are operable to transfer a substrate from one station to the next without exposing the substrate to the external environment. In one embodiment, the apparatus of the present invention is operable to transfer the substrate from one station to the next without breaking vacuum, and may include operable to deposit lithium from a source of lithium-containing material on the electrochromic device. One or more lithiation sites on one or more layers. In one embodiment, the apparatus of the present invention is operable to deposit the electrochromic stack on an architectural glass substrate. In an embodiment, the apparatus is operable to transfer the substrate from one stage to the next without breaking vacuum. In another embodiment, the integrated deposition system further comprises one of or operable to deposit lithium from a lithium-containing material source on at least one of the electrochromic layer, the intermediate layer, and the counter electrode layer. Multiple lithiation stations. In yet another embodiment, the integrated deposition system is operable to deposit the stack on an architectural glass substrate. In another embodiment, the integrated deposition system further includes a substrate holder and a transport mechanism operable to hold the architectural glass substrate in a vertical orientation as the architectural glass substrate is passed through the integrated deposition system. In another embodiment, the apparatus further comprises one or more load locks for transferring the substrate between an external environment and the integrated deposition system. In another embodiment, the apparatus further comprises at least one slit valve operable to permit the one or more lithium deposition stations and at least one of the first deposition station and the second deposition station isolated. In one embodiment, the integrated deposition system includes one or more heaters configured to heat the substrate. 5 depicts a simplified representation of an integrated deposition system 500 in perspective view and includes a cross-sectional view of the interior in more detail. In this example, system 500 is a module in which inlet 502 and outlet 504 are connected to a deposition module 506 . There is an inlet port 510 (the vacuum chamber 504 has a corresponding outlet port) for loading, for example, an architectural glass substrate 525 . Substrates 525 are supported by pallets 520 that travel along rails 515 . In this example, the pallet 520 is supported by the rail 515 via suspension, but the pallet 520 could also be supported on a rail located near the bottom of the apparatus 500 or between the top and bottom of the apparatus 500, for example. top. The pallet 520 can translate forward and/or backward in the system 500 (as indicated by the double-headed arrow). For example, during lithium deposition, the substrate can be moved forward and backward in front of the lithium target 530, resulting in multiple passes to achieve the desired lithiation. However, this functionality is not limited to lithium targets, for example, a tungsten target can be passed multiple times over a substrate, or the substrate can be passed in front of the tungsten target via a forward/backward motion path to deposit, for example, an electrochromic layer. Pallet 520 and substrate 525 are in a substantially vertical orientation. The substantially vertical orientation is not limiting, but it can help prevent defects because particulate matter, which may for example arise from the coalescence of atoms from sputtering, will tend to be gravitational and thus not deposited on the substrate 525 . Also, because architectural glass substrates tend to be large, the vertical orientation of the substrates enables the coating of thinner glass substrates as it traverses the stages of the integrated deposition system because of the effects on thicker thermal glass. There is less concern about sagging. Target 530 , in this case a cylindrical target, is oriented substantially parallel to and in front of the substrate surface on which deposition will occur (other sputtering means are not depicted here for convenience). Substrate 525 may translate past target 530 during deposition, and/or target 530 may move in front of substrate 525 . The path of movement of the target 530 is not limited to translation along the path of the substrate 525 . The target 530 can be rotated along an axis through its length, translated along a path of the substrate (forward and/or backward), translated along a path perpendicular to the path of the substrate, circular in a plane parallel to the substrate 525 path movement, etc. The target 530 need not be cylindrical, it can be flat or any shape needed to deposit the desired layer with the desired properties. Also, there may be more than one target in each deposition station, and/or targets may move between stations depending on the desired process. The various stations of the integrated deposition system of the present invention may be modules, but once connected form a continuous system in which a controlled ambient environment is established and maintained for processing substrates at the various stations within the system. More detailed aspects of how to deposit electrochromic materials using the integrated deposition system 500 are described in the aforementioned US Nonprovisional Patent Application Nos. 12/645,111 and 12/645,159. The integrated deposition system 500 also has various vacuum pumps, gas inlets, pressure sensors, and the like to establish and maintain a controlled ambient environment within the system. Such components are not shown, but would be understood by those of ordinary skill in the art. System 500 is controlled, for example, via a computer system or other controller represented by LCD and keypad 535 in FIG. 5 . Those of ordinary skill in the art will appreciate that embodiments of the invention may employ a variety of processes involving data stored on or transmitted through one or more computer systems. Embodiments of the invention also relate to devices for performing these operations, such computers and microcontrollers. Such equipment and processes can be used to deposit the electrochromic materials of the methods of the present invention and devices designed to carry out the methods. The control device of the present invention may be specially constructed for the required purpose, or the control device may be a general purpose computer selectively activated or reconfigured by computer programs and/or data structures stored in the computer. The programs presented herein are not inherently tied to any particular computer or other device. In particular, various general purpose machines may be used with programs written in accordance with the teachings herein, or it may be more convenient to construct more specific apparatus to execute and/or control the desired methods and programs. As can be seen from the description above (particularly of FIGS. 3A-3B ), using the method of the present invention, one can fabricate not only electrochromic devices, but also pre-fabricated layered stacks (eg, 400, 403, and 409 ), which in some Cases may be converted to electrochromic devices via subsequent processing such as described herein. Such "electrochromic device precursors" may be of particular value, although not functional electrochromic devices because they do not have an ionically conductive and electrically insulating region between the EC layer and the CE layer. This is especially the case where the device precursors are fabricated at high purity in an integrated processing facility as described herein, where the material layers are all deposited in a controlled ambient environment in which the vacuum is never broken, for example. In this way, high-purity low-defect materials are stacked and substantially "sealed," eg, by the final TCO layer and/or capping layer, before leaving the integrated system. As with the electrochromic device of the present invention described above, the electrochromic device precursor may also include one or more additional layers (not shown) such as one or more passive layers (not shown), for example, to modify certain optical properties (providing moisture or scratch resistance) to hermetically seal the device precursors and the like. In one embodiment, a capping layer is deposited on the TCO layer of the precursor stack. In some embodiments, the capping layer is SiAlO. In some embodiments, the capping layer is deposited by sputtering. In one embodiment, the thickness of the capping layer is between about 30 nm and about 100 nm. Subsequent processing of the cap layer in place forms the IC layer without contamination from the environment, ie, with the additional protection of the cap layer. Conversion to a functional electrochromic device can, if desired, occur outside the integrated system because the internal stack is protected from the external environment and conditions of somewhat less stringent purity are used to convert the precursors Necessary for the final conditioning step to convert the stack into a functional device. Such stacked electrochromic device precursors may have advantages, for example, due to a longer lifetime of switching to the electrochromic device only when needed, by having, for example, storability and where the switching parameters depend on the final product Flexibility resulting from a single precursor stack for use in conversion that requires and must meet quality standards that can be modified or fed to different conversion chambers and/or points of consumption for conversion. Again, such precursor stacks can be used for testing purposes, eg, quality control or research efforts. Therefore, one embodiment of the present invention is an electrochromic device precursor, which includes: (a) a substrate; (b) a first transparent conductive oxide layer on the substrate; (c) the first transparent conductive oxide A stack on a layer, the stack comprising: (i) an electrochromic layer comprising an electrochromic material, and (ii) a counter electrode layer comprising a counter electrode material; wherein the stack does not comprise an electrochromic layer between the electrochromic layer an ionically conductive and electrically insulating region from the counter electrode layer; and (d) a second transparent conductive oxide layer on top of the stack. In one embodiment, the electrochromic layer includes tungsten oxide, and the counter electrode layer includes nickel-tungsten oxide. In one embodiment, at least one of the stack and the electrochromic layer contains lithium. In another embodiment, the electrochromic layer is tungsten oxide having a superstoichiometric oxygen content at least at the interface with the counter electrode layer. In another embodiment, the stack includes an IC precursor layer between the counter electrode layer and the electrochromic layer, the IC precursor layer comprising Oxygen Tungsten Oxide. In one embodiment, in the absence of an IC precursor layer between the EC layer and the CE layer, the thickness of the electrochromic layer is between about 500 nm and about 600 nm, and the thickness of the counter electrode layer is Between about 150 nm and about 300 nm. In another embodiment, where there is an IC precursor layer between the EC layer and the CE layer, the thickness of the electrochromic layer is between about 350 nm and about 400 nm, the thickness of the IC precursor layer is between between about 20 nm and about 100 nm, and the thickness of the opposite electrode layer is between about 150 nm and about 300 nm. In one embodiment, the precursor devices described herein are exposed to heat to convert the devices into functional electrochromic devices. In one embodiment, heating is part of the MTCC. Another embodiment is an electrochromic device comprising: (a) an electrochromic layer comprising an electrochromic material; and (b) a counter electrode layer comprising a counter electrode material, wherein the device does not contain A compositionally homogeneous layer of electrically insulating ion-conducting material between the electrochromic layer and the counter electrode. In one embodiment, the electrochromic material is tungsten oxide, the counter electrode material is nickel tungsten oxide, and the layer between the electrochromic layer and the counter electrode layer includes lithium tungstate and tungsten oxide. and an interface region of a mixture of at least one of nickel and tungsten oxide. In another embodiment, the thickness of the electrochromic layer is between about 300 nm and about 500 nm; the thickness of the interface region is between about 10 nm and about 150 nm, and the thickness of the counter electrode layer is between Between about 150 nm and about 300 nm. EXAMPLES FIG. 6 is a graph of a process flow used as a scheme for fabricating electrochromic devices of the present invention. The y -axis units are optical density and the x -axis units are time/program flow. In this example, an electrochromic device similar to that described with respect to FIG. 4A was fabricated in which the substrate was glass with fluorinated tin oxide as the first TCO and the EC layer was a glass with excess oxygen in the matrix. WO3 ₍ e.g., sputtered using a tungsten target, where the sputtering gas is about 60% _O2 and about 40% Ar), the CE layer is formed on top of the EC layer and is made of NiWO, and the second TCO is Indium tin oxide (ITO). Lithium was used as ion source for the electrochromic transition. Optical density is used to determine endpoints during fabrication of electrochromic devices. Optical density was measured as the EC layer (WO3 ₎ was deposited on the substrate (glass+TCO) starting from the origin of the graph. The optical density of the glass substrate had a baseline optical density of about 0.07 (absorbance units). As the EC layer builds, the optical density increases from this point because tungsten oxide (although substantially transparent) absorbs some visible light. For a desired thickness of a tungsten oxide layer of about 550 nm thick, the optical density rises to about 0.2 as described above. After depositing the tungsten oxide EC layer, lithium was sputtered on the EC layer, as indicated by the first time period indicated by "Li". During this period, the optical density increases further along the curve to 0.4, which indicates that the blind charge of tungsten oxide has been satisfied due to the coloring of tungsten oxide with lithium addition. The time period indicated by "NiWO" indicates the deposition of the NiWO layer during which the optical density increases because the NiWO is colored. Due to the addition of an approximately 230 nm thick NiWO layer, the optical density further increased from approximately 0.4 to approximately 0.9 during NiWO deposition. Note that some lithium can diffuse from the EC layer to the CE layer as NiWO is deposited. This serves to maintain the optical density at a relatively low value during NiWO deposition, or at least during the initial stages of deposition. The second time period indicated by "Li" indicates the addition of lithium to the NiWO EC layer. The optical density decreased from about 0.9 to about 0.4 during this stage due to the discoloration of NiWO by lithiation of NiWO. Lithiation was performed until the NiWO faded (including a local minimum of optical density at about 0.4). The optical density starts to pick up around 0.4 because the WO ₃ layer is still lithiated and affects the optical density. Next, additional lithium was sputtered onto the NiWO layer as indicated by the time period "Extra Li", in this example about 10% of the additional lithium compared to the lithium added to NiWO discolored the NiWO layer. During this phase, the optical density increases slightly. Next, indium tin oxide TCO is added, as indicated by "ITO" in the graph. Again, the optical density continued to rise slightly to about 0.6 during the formation of the ITO layer. Next, as indicated by the time period indicated by "MSTCC", the device was heated to about 250°C under Ar for about 15 minutes, and then heated under _O2 for about 5 minutes. Next, the device was annealed at about 300° C. for about 30 minutes in air. During this time, the optical density decreased to about 0.4. Thus, optical density is useful in fabricating devices of the present invention (e.g., for determining layer thickness based on deposited material and morphology, and especially for titrating lithium onto various layers for satisfying blind charges and/or achieving fading status) useful tool. Consistent with the approach described with respect to Figure 6, Figure 7 shows a cross-sectional TEM of an electrochromic device 700 fabricated using the method of the present invention. Device 700 has a glass substrate 702 on which an electrochromic stack 714 is formed. Substrate 702 has an ITO layer 704 acting as a first TCO. Tungsten oxide EC layer 706 is deposited on TCO 704 . Layer 706 was formed at a thickness of approximately 550 nm (ie, WO3 formed by sputtering tungsten with oxygen and argon), as described above with respect to FIG. ₆ . Lithium is added to the EC layer. Next, an approximately 230 nm thick NiWO CE layer 710 is added, followed by lithium for decolorization and then an approximately 10% excess lithium. Finally, an indium tin oxide layer 712 is deposited, and the stack is subjected to multi-step thermochemical conditioning, as described above with respect to Figure 4A. After MSTCC, this TEM was performed. As can be seen, a new region 708 of ion conducting and electrically insulating is formed. Figure 7 also shows five selected area electron diffraction (SAED) patterns for various layers. First, 704a indicates that the ITO layer is highly crystalline. Pattern 706a shows that the EC layer is polycrystalline. Pattern 708a shows that the IC layer is substantially amorphous. Pattern 710a shows that the CE layer is polycrystalline. Finally, pattern 712a shows that the indium tin oxide TCO layer is highly crystalline. Figure 8 is a cross-section of a device 800 of the present invention analyzed by scanning transmission electron microscopy (STEM). In this example, consistent with the scheme described with respect to Figure 4B, device 800 was fabricated using the methods of the present invention. Device 800 is an electrochromic stack formed on a glass substrate (not labeled). On the glass substrate is a layer of fluorinated tin oxide 804 that acts as the first TCO (for transparent electronic conductors, this layer is sometimes referred to as the "TEC" layer). Tungsten oxide EC layer 806 is deposited on TCO 804 . In this example, layer 806 is formed at a thickness _of about 400 nm (i.e., WO3 formed by sputtering tungsten with oxygen and argon, as described above with respect to FIG. About 150 nm thick. Lithium is added to layer 805 . Next, an approximately 230 nm thick NiWO CE layer 810 is added, followed by lithium for decolorization and then an approximately 10% excess lithium. Finally, an indium tin oxide layer 812 is deposited and the stack is subjected to multi-step thermochemical conditioning, as described above with respect to Figure 4B. After MSTCC, do this STEM. As can be seen, a new region 808 of ion conducting and electrically insulating is formed. The difference between this example and the embodiment described with respect to FIG. 4B is that, unlike the similar layer 405 in FIG. 4B , the oxygen-rich layer 805 is only partially converted into an interfacial region 808 . In this case, only about 40 nm of the 150 nm of the oxygen-rich precursor layer 405 is converted into a region that acts as an ion-conducting layer. Figures 8B and 8C show a "before and after" comparison of the device 800 of the present invention (Figure 8C) with the device precursor prior to multi-step thermochemical conditioning (Figure 8B) as analyzed by STEM. In this example, only layers 804-810 (EC to CE) are depicted. The layers are numbered the same as in Figure 8A, with some exceptions. The dotted line in FIG. 8B is used to roughly distinguish the interface between the EC layer 806 and the oxygen-enriched layer 805 (which is more clearly shown in FIG. 8C ). Referring again to Figure 8B, it appears that there is at least lithium concentrated at the interface of the oxygen-rich layer 805 and the CE layer 810 (approximately 10-15 nm thick region), as indicated by 808a. After MTCC (FIG. 8C), it is evident that an interfacial region 808 has formed. While the foregoing invention has been described in some detail to facilitate understanding, the described embodiments should be considered illustrative rather than restrictive. It will be apparent to those of ordinary skill in the art that certain changes and modifications may be practiced within the scope of the appended claims.

100: Electrochromic device 102: Substrate 104: Conductive layer (CL) 106: Electrochromic (EC) layer 108: Ion conduction (IC) layer 110: Counter electrode (CE) layer 112: Conductive layer (CL) 114 : Electrochromic stack 116: Voltage source 300: Program flow 320: Program flow 400: Layered structure 401: Functional electrochromic device 402: Substrate 403: Layered structure 404: First TCO layer 405: Second WO ₃ Layer 406: EC layer 406a: EC layer 407: layered stack 408: IC layer/interface region 408a: ion conducting electrically insulating region/interface region 408b: graded interface region 409: layered structure 410: CE layer 411: layered stack /Functional electrochromic device 412: second TCO layer 414a: stack 414b: stack 414c: stack 500: integrated deposition system 502: entrance vacuum pre-pumping chamber 504: exit vacuum pre-pumping chamber 506: deposition module 510: entrance Port 515: Track 520: Pallet 525: Substrate 530: Lithium Target 535: LCD and Keypad 700: Electrochromic Device 702: Glass Substrate 704: Indium Tin Oxide (ITO) Layer 704a: Pattern 706: Tungsten Oxide EC Layer 706a: pattern 708: new area 708a: pattern 710: CE layer 710a: pattern 712: indium tin oxide layer 712a: pattern 714: electrochromic stack 800: device 804: fluorinated tin oxide layer 805: oxygen-enriched precursor layer 806: Tungsten Oxide EC Layer 808: New Area/Interface Area 808a: Lithium 810: CE Layer 812: Indium Tin Oxide Layer

Figure 1A is a schematic cross section depicting the conventional formation of an electrochromic device stack. FIG. 1B is a graph showing the composition of the EC layer, the IC layer and the CE layer in a conventional electrochromic stack. 2A-2C are graphs showing representative component compositions for electrochromic devices of the present invention. 3A and 3B are process flows according to an embodiment of the present invention. 4A-4C are schematic cross-sections depicting the formation of an electrochromic device according to certain embodiments of the invention. Figure 5 depicts the integrated deposition system of the present invention in perspective view. 6 is a graph showing how program parameters and endpoint indication readings relate during formation of an electrochromic stack according to an embodiment of the invention. 7 and 8A-8C are actual cross-sections of electrochromic devices fabricated using methods according to embodiments of the present invention.

320: Program flow

Claims (24)

A method of forming an electrochromic device, the method comprising: (a) Depositing an electrochromic layer on a substrate; (b) deposit metal on the electrochromic layer; and (c) Oxidizing at least a portion of the metal to form an ionically conductive and electrically insulating material. The method according to claim 1, wherein the metal is lithium. The method of claim 2, wherein the ionically conductive and electrically insulating material comprises at least one material selected from the group consisting of lithium tungstate (Li ₂ WO ₄ ), lithium molybdate (Li ₂ MoO ₄ ), lithium niobate ( LiNbO ₃ ), lithium tantalate (LiTaO ₃ ), lithium titanate (Li ₂ TiO ₃ ), lithium zirconate (Li ₂ ZrO ₃ ), and combinations thereof. The method of claim 3, wherein the electrochromic layer comprises tungsten oxide and the ion-conducting and electrically insulating material comprises lithium tungstate. The method of claim 3, wherein the electrochromic layer comprises molybdenum oxide and the ionically conductive and electrically insulating material comprises lithium molybdate. The method of claim 3, wherein the electrochromic layer comprises niobium oxide and the ionically conductive and electrically insulating material comprises lithium niobate. The method of claim 3, wherein the electrochromic layer comprises tantalum oxide and the ionically conductive and electrically insulating material comprises lithium tantalate. The method of claim 3, wherein the electrochromic layer comprises titanium oxide and the ionically conductive and electrically insulating material comprises lithium titanate. The method of claim 3, wherein the electrochromic layer comprises zirconia and the ionically conductive and electrically insulating material comprises lithium zirconate. The method of claim 1, wherein oxidizing at least a portion of the metal to form the ionically conductive and electrically insulating material comprises exposing the substrate and/or the metal to oxygen. The method of claim 10, wherein the oxygen is provided as part of the electrochromic layer. The method of claim 10, further comprising depositing a counter electrode layer, wherein the oxygen is provided as part of the counter electrode layer. The method of claim 10, wherein the oxygen system is provided as a superstoichiometric oxygen material on the substrate. The method of claim 10, wherein the oxygen is provided in an atmosphere to which the substrate is exposed. The method of claim 1, wherein oxidizing at least a portion of the metal to form the ionically conductive and electrically insulating material comprises heating the substrate. The method of claim 15, wherein heating the substrate causes a reaction between the metal and the material of the electrochromic layer to form the ionically conductive and electrically insulating material. The method of claim 15, further comprising depositing a counter electrode layer, wherein heating the substrate causes a reaction between the metal and a material of the counter electrode layer to form the ionically conductive and electrically insulating material. The method of claim 1, further comprising depositing a counter electrode layer, wherein oxidizing at least a portion of the metal to form the ionically conductive and electrically insulating material occurs before depositing the counter electrode layer. The method of claim 1, further comprising depositing a counter electrode layer, wherein oxidizing at least a portion of the metal to form the ionically conductive and electrically insulating material occurs when depositing the counter electrode layer. The method of claim 1, further comprising depositing a counter electrode layer, wherein oxidizing at least a portion of the metal to form the ion conducting and electrically insulating material occurs after depositing the counter electrode layer. The method of claim 1, further comprising depositing a counter electrode layer, and depositing additional metal on the counter electrode layer. The method of claim 21, wherein the additional metal is sufficient to completely discolor the counter electrode layer. The method of claim 1, wherein (a) and (b) are performed under vacuum, and wherein the vacuum is not broken between (a) and (b). The method according to claim 1, wherein the metal is selected from the group consisting of lithium, sodium, potassium, calcium, barium, strontium, magnesium and combinations thereof.

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