EP2510534A2 - Dispositif et procédé de modification d'un substrat semiconducteur par un faisceau d'ions - Google Patents

Dispositif et procédé de modification d'un substrat semiconducteur par un faisceau d'ions

Info

Publication number
EP2510534A2
EP2510534A2 EP10790430A EP10790430A EP2510534A2 EP 2510534 A2 EP2510534 A2 EP 2510534A2 EP 10790430 A EP10790430 A EP 10790430A EP 10790430 A EP10790430 A EP 10790430A EP 2510534 A2 EP2510534 A2 EP 2510534A2
Authority
EP
European Patent Office
Prior art keywords
ion
semiconductor substrate
array
unit
annealing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP10790430A
Other languages
German (de)
English (en)
Inventor
Frank Machalett
Jan Lossen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Robert Bosch GmbH
Original Assignee
Robert Bosch GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of EP2510534A2 publication Critical patent/EP2510534A2/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/30—Electron-beam or ion-beam tubes for localised treatment of objects
    • H01J37/317—Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. for ion implantation
    • H01J37/3171—Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. for ion implantation for ion implantation
    • H01J37/3172—Maskless patterned ion implantation
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P30/00—Ion implantation into wafers, substrates or parts of devices
    • H10P30/20—Ion implantation into wafers, substrates or parts of devices into semiconductor materials, e.g. for doping
    • H10P30/21—Ion implantation into wafers, substrates or parts of devices into semiconductor materials, e.g. for doping of electrically active species
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/02—Details
    • H01J37/04—Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement or ion-optical arrangement
    • H01J37/08—Ion sources; Ion guns
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F10/00—Individual photovoltaic cells, e.g. solar cells
    • H10F10/10—Individual photovoltaic cells, e.g. solar cells having potential barriers
    • H10F10/14—Photovoltaic cells having only PN homojunction potential barriers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F10/00—Individual photovoltaic cells, e.g. solar cells
    • H10F10/10—Individual photovoltaic cells, e.g. solar cells having potential barriers
    • H10F10/14—Photovoltaic cells having only PN homojunction potential barriers
    • H10F10/146—Back-junction photovoltaic cells, e.g. having interdigitated base-emitter regions on the back side
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F71/00—Manufacture or treatment of devices covered by this subclass
    • H10F71/121—The active layers comprising only Group IV materials
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F77/00—Constructional details of devices covered by this subclass
    • H10F77/20—Electrodes
    • H10F77/206—Electrodes for devices having potential barriers
    • H10F77/211—Electrodes for devices having potential barriers for photovoltaic cells
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F77/00—Constructional details of devices covered by this subclass
    • H10F77/20—Electrodes
    • H10F77/206—Electrodes for devices having potential barriers
    • H10F77/211—Electrodes for devices having potential barriers for photovoltaic cells
    • H10F77/219—Arrangements for electrodes of back-contact photovoltaic cells
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P30/00—Ion implantation into wafers, substrates or parts of devices
    • H10P30/20—Ion implantation into wafers, substrates or parts of devices into semiconductor materials, e.g. for doping
    • H10P30/202—Ion implantation into wafers, substrates or parts of devices into semiconductor materials, e.g. for doping characterised by the semiconductor materials
    • H10P30/204—Ion implantation into wafers, substrates or parts of devices into semiconductor materials, e.g. for doping characterised by the semiconductor materials into Group IV semiconductors
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P30/00—Ion implantation into wafers, substrates or parts of devices
    • H10P30/20—Ion implantation into wafers, substrates or parts of devices into semiconductor materials, e.g. for doping
    • H10P30/28—Ion implantation into wafers, substrates or parts of devices into semiconductor materials, e.g. for doping characterised by an annealing step, e.g. for activation of dopants
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H10P72/04—Apparatus for manufacture or treatment
    • H10P72/0431—Apparatus for thermal treatment
    • H10P72/0436—Apparatus for thermal treatment mainly by radiation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/06—Sources
    • H01J2237/08—Ion sources
    • H01J2237/0802—Field ionization sources
    • H01J2237/0805—Liquid metal sources
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/06—Sources
    • H01J2237/08—Ion sources
    • H01J2237/0802—Field ionization sources
    • H01J2237/0807—Gas field ion sources [GFIS]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/20—Positioning, supporting, modifying or maintaining the physical state of objects being observed or treated
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/30—Electron or ion beam tubes for processing objects
    • H01J2237/317—Processing objects on a microscale
    • H01J2237/31701—Ion implantation
    • H01J2237/31706—Ion implantation characterised by the area treated
    • H01J2237/3171—Ion implantation characterised by the area treated patterned
    • H01J2237/31713—Focused ion beam
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/30—Electron or ion beam tubes for processing objects
    • H01J2237/317—Processing objects on a microscale
    • H01J2237/31749—Focused ion beam
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/547—Monocrystalline silicon PV cells
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

  • the diffusion process is a high-temperature process using solid-state diffusion processes. In the doping of Al in Si while temperatures of up to 1100 ° C and more are needed. The process is thus energy and costly. In addition, at temperatures of more than 900 ° C., Al-O complexes can form in the doping region, which have a negative effect on the lifetime of the charge carriers generated in the doping region or on the lattice structure on which they are based.
  • the penetration depth of the ions depends on the position of the crystal planes in the substrate to be doped.
  • stencils or masks are used in the known doping methods and, in particular, also in conventional ion implantations, which are applied to the semiconductor substrate or introduced into the beam path. When masks are used, the ion beam irradiated over a large area is not used during the entire time or is ultimately consumed inconclusively in the area of the mask. As a result, the time required for the implantation increases very strongly.
  • an apparatus for ion beam modification on a semiconductor substrate having the features of claim 1 and a method for ion beam modification on a semiconductor substrate with the features of claim 18 are provided.
  • the subclaims contain expedient and / or advantageous embodiments of the device and method.
  • the device according to the invention for on-beam modification on a semiconductor substrate is formed with at least two field emission microionic radiators with an array arrangement aligned with the semiconductor substrate. These each consist of an ion emitter with an ion source reservoir, an extractor, and / or an electrostatic lens and / or a post-acceleration unit at respectively different electrical potentials.
  • the idea underlying the device according to the invention is therefore to use field emission arrangements for ion beam modification.
  • Such field emission arrangements are known in the field of ion drives.
  • Another aspect of the inventive concept is to provide more than just a micro-ion radiator and the
  • the ion emitter various devices can be used.
  • the ion emitter is formed as a gas field ion source.
  • the ion emitter is formed as a liquid metal ion source, wherein the liquid metal ion source contains in a melt miscible doping components and / or material components of the semiconductor substrate.
  • the melt-miscible doping component may be formed as a eutectic melt.
  • the annealing unit is formed as part of an annealing array which interacts with the array arrangement of the micro-ion radiators and comprises at least two annealing units.
  • the array of microionic emitters in conjunction with the annealing array thereby form a group that can be acted upon by control signals with which the desired modification regions and profiles can be inscribed or embossed into the semiconductor substrate.
  • a control unit is provided for this purpose, with which a single response of the micro-ion radiators in the array unit and / or a single response of the annealing units in the annealing array is executable.
  • a feed unit addressed by the control unit is provided for a relative movement between the array unit and the semiconductor substrate which generates the modification pattern.
  • the annealing irradiation from the ion irradiation side can be in situ, e.g. B. by oblique injection of Annealingbestrahlung, or alternately by periodic displacement of the semiconductor substrate between the two arrays.
  • the location-dependent adjustable depth of the modification profile is generated by a controlled post-acceleration of the ion beam at the respective field emission microionic emitter of the array arrangement.
  • the ions are thereby provided at the individual micro-ion radiators with different pulse amounts or different energies and thus penetrate into the semiconductor substrate at pre-planned different points at different depths to form the desired depth structure.
  • an electrostatic deflection and / or a relative movement of the semiconductor substrate with respect to the ion beam is carried out.
  • an energy filter effects and / or suppresses a droplet or neutral pond beam component.
  • Fig. 3 is an illustration of a micro-ion radiator with an associated
  • 4b shows an exemplary representation of an array unit with an over
  • FIG. 5 shows a micro ion gun with a needle type ion source in FIG.
  • FIG. 1 a view of an exemplary ExB filter and its effect as.
  • the basic concept of the exemplary embodiments described below is to transfer the principle of so-called field emission thrusters or field emission thrusters in the form of the microionic emitters to the modification, in particular the doping, of semiconductor substrates.
  • the process steps and devices described by way of example above are doped rapidly and with minimal effort.
  • Al, Ga and In are used as doping materials.
  • Doping with other dopants in particular B, P, As or Sb, is also possible in principle, but it requires a special preparation of precursor materials for these dopable materials that can not be used in pure state in liquid metal ion sources.
  • the demands on the precursor or ion source substances are a low melting point, a low saturation vapor pressure, good wettability and the negligible chemical reaction with the high-melting emitter capillaries or emitter capillaries (eg W, Mo, glass-C).
  • liquid metal ion sources are first described in the following description. These work as field emission sources with a high directional beam value or bright- ness of approx. 10 6 A / (cm 2 sr).
  • the unit of measurement stands for "amperes per square centimeter and steradian", Steradian being the unit of measurement for a solid angle, the emitters thus formed being small and having an extraordinarily high size
  • these micro-ion emitters can be turned on or off as it were in pixels. This makes a structured implantation possible. It is particularly important to avoid temperatures of more than 1000 ° C, which may otherwise lead to the formation of so-called metal-oxygen complexes in the semiconductor material.
  • the ion current impinging on the semiconductor substrate is increased by several orders of magnitude.
  • the first advantage reduces the cost of the system relative to the implanted ion current by at least one to two orders of magnitude, the second accelerates the throughput of the semiconductor substrates to be doped by reducing the irradiated area to the area actually required for implantation. Losses due to the use of doping masks are eliminated.
  • the ions can be post-accelerated, whereby the depth of the doping can be adjusted.
  • grid units according to the principle of electrostatic capacitors laterally homogeneous doping can be achieved or structures are generated.
  • droplet or neutral particle emissions can be masked by various measures.
  • individual embodiments will be described in more detail.
  • the basic principle of the invention is pursued, which is to make the structure always as simple and convenient as possible and to integrate only those ion-optical or structural elements in the device, which are required for the particular purpose.
  • the optimized for each application device should be as cost effective as possible.
  • the microionic emitter consists of a field emission arrangement which is directed onto a semiconductor substrate 2 and generates there an implantation region 2a by means of the ion beam.
  • the field emission arrangement comprises an ion emitter 3 with an ion reservoir 4, which in the present example is formed as a melt.
  • the melt is, for example, aluminum, gallium or an alloy of aluminum or gallium with the material of the semiconductor substrate, for example silicon.
  • the ion emitter and the ion source reservoir are at a first electrical potential.
  • the ion emitter 3 is followed by an extractor 5 in the direction of the implantation area.
  • the electrical voltage between extractor and emitter tip serves to generate a field strength at the emitter tip, which is sufficient to transform the melt into a conical protuberance, a so-called Taylor cone, from whose peak the ion emission can take place.
  • the regulation and stabilization of the ion current can be done by varying the extraction voltage or by introducing a control electrode with an opening in the immediate vicinity of the emission point or something behind it.
  • a focusing of the ion beam is not provided in this simple structure.
  • the extractor is at a further electrical potential and thus accelerates the ions emanating from the ion emitter. If focusing of the ion beam is required, an electrostatic lens 6 may be used.
  • the extractor cooperates with the electrostatic lens 6. This usually has the same electrostatic potential as the extractor and serves either to focus the ion beam onto the implantation area or to parallelize the initially diverging trajectories of the ions.
  • the representation is only in principle. As electrostatic lens, a complete single lens with three pinhole or cylinders can be used.
  • this f ocussing and collimating structure can be supplemented by a post-acceleration unit 7.
  • This is zero in potential with respect to the ionic emitter, extractor and electrostatic lens potentials.
  • the potential difference applied between the ion emitter and the post-acceleration unit thus ultimately causes the ion acceleration and is decisive for the achievable penetration depth of the ion beam in the substrate surface and the thereby producible
  • Fig. 1 shows a first example of this.
  • the electrostatic lens 6 is formed as a lens system 6a and 6b, while the post-acceleration unit 7 consists of two individual electrodes 7a and 7b.
  • the post-acceleration unit 7 consists of two individual electrodes 7a and 7b.
  • a beam deflection unit 8 is also provided between the electrostatic lens 6 and the post-acceleration unit 7.
  • capacitor plates 8a, 8b serves for a directional deflection of the ion beam and a removal of ejected from the ion source material droplets. These are driven by their mass inertia as well as by their increased compared to the ion current energy width from the ion beam against the capacitor plates of the beam deflection unit 8 and thus removed from the ion beam.
  • the capacitor is designed, for example, as a cylindrical capacitor.
  • an increase in the droplet emission under certain circumstances may be advantageous and desirable.
  • This can be achieved by a suitable choice of ionic emitter and by higher emission currents. It is possible to use a capillary type emitter instead of a needle type emitter and an emission current of more than 10 ⁇ .
  • metal can be deposited finely distributed, wherein a conventional alloy doping or a coating can be produced by a thermal treatment.
  • the droplets generated are deposited as micro- and nanodroplets on the semiconductor substrate.
  • the ion emitter both in its embodiment as a needle emitter and in its embodiment as a capillary emitter of a glassy carbon material or be covered with a protective layer, in particular Al 2 0 3 , to avoid a reaction of the melt with the source material.
  • a protective layer in particular Al 2 0 3 , to avoid a reaction of the melt with the source material.
  • Such a configuration is particularly in an ion emitter into consideration, which is to serve for the emission of Al ions.
  • the ion beams may be additionally electrostatically deflected, i. H. be wobbled.
  • the semiconductor substrate and the beam may be moved relative to each other.
  • a Wehnelt control electrode (not shown here) may be added to the structure formed in FIGS. 1 and 2. By spraying the Wehnelt electrode, the ion beam can be defocused with a short response time or completely blanked out.
  • Annealingü be supplemented. This heals the material defects possibly arising in the implantation area in situ or immediately afterwards.
  • Fig. 3 shows a related example.
  • the annealing unit 9 is arranged on the rear side of the semiconductor substrate 2. It is designed here as a laser unit whose beam direction is opposite to the direction of the ion beam from the micro-ion radiator.
  • the annealing unit thus acts on the back of the implantation area. This achieves an in situ healing of the implantation defects, which can be carried out simultaneously with the implantation itself.
  • both the micro-ion radiator and the annealing unit can be operated simultaneously and in parallel and act on the implantation area.
  • the mode of operation of the annealing unit is based on a local heating of the implantation area and a local annealing of the radiation damage in the semiconductor substrate caused thereby.
  • an energy supply by means of Laser radiation as in the present example also comes into consideration other radiation sources, such as I R or microwave radiators into consideration.
  • the implantation array combines a plurality of the above-explained micro-ion radiators 1 as a unit. These are acted upon by a control unit, not shown here with control signals. In this way, first of all, individual ion streams can be triggered in each of the microionic emitters, which, secondly, are also emitted with a different kinetic energy and, thirdly, a different focusing state. In conjunction therewith, the penetration depth and the lateral extent of each implantation region 2a change under each of the individual microionic emitters. As a result, a three-dimensional implantation profile can thereby be generated in the semiconductor substrate. Through the use of the implantation array, this implantation profile is generated virtually simultaneously in a single work step and thus in a short time.
  • the implantation array 10 corresponds to the opposite annealing array 11 located on the other side of the semiconductor substrate 2.
  • This consists of a series of annealing units 9 which are also supplied with control signals, in particular turn-on and turn-off signals and control signals for intensity control, by a control unit not shown here.
  • control signals in particular turn-on and turn-off signals and control signals for intensity control, by a control unit not shown here.
  • the direction of action of the annealing array 11 is opposite to the beam direction of the implantation array 10.
  • each individual micro-radiator 1 is in each case opposite and assigned an annealing unit 9 is.
  • the operating parameters of each individual micro-ion radiator are matched with the operating parameters of the respective opposing annealing unit. This means, for example, that an annealing unit is activated only when the opposite infrared radiator is active. Furthermore, there is an in situ adaptation between the operation of the micro-ion radiator with the operation of the associated annealing unit.
  • the intensity of the corresponding annealing unit is likewise reduced or distributed to a larger irradiation area by means of an enlargement optics. Because the annealing unit acts on the implantation region from the rear side of the semiconductor substrate, the absorption of the semiconductor substrate as well as its heat conduction must be taken into account. If the semiconductor substrate is thin, it can be assumed that the heat introduced by the annealing unit is introduced into the implantation area largely without loss. Additional details may need to be determined in series and trials.
  • FIG. 4a shows an exemplary representation of an array unit with a tracking annealing array.
  • the array unit 10 is first passed over the semiconductor substrate 2. In this case, ion beam modification or doping of the surface is undertaken. Subsequently, the semiconductor substrate is placed under the annealing array 11
  • FIG. 4b shows an exemplary representation of an array unit with an annealing applied via mirrors.
  • the annealing pattern is imaged onto the semiconductor substrate in such a way that a mirror device (not shown here) drives the individual points of the modified surface and carries out local annealing there. This process can be carried out both in situ and immediately after the modification.
  • the annealing takes place by a simultaneous input of energy
  • the array unit 10 is moved away relative to the semiconductor substrate while subsequently the mentioned activation of the individual modification points takes place on the semiconductor surface.
  • micro-ion emitters enable irradiation times which are shortened by up to three to five orders of magnitude compared to those of conventional high-current implanters. The throughput times are reduced accordingly. Consideration must be given to the deposited ionic energy, which can lead to local warming but can be controlled by the ion current and the irradiation intervals. However, this local warming can also contribute to the self-healing of radiation damage, since it is the largest where the highest density of radiation damage is produced.
  • the devices shown in Figures 4 to 4b are advantageously operated so that a large number of semiconductor substrates are simultaneously introduced into a vacuum chamber and processed at a high throughput.
  • small vacuum chambers are also possible, into which the substrates are introduced individually or in small groups.
  • a particularly good range of the ion current in the semiconductor substrate is achieved by a vertical, channeled injection of the ions in the [100] oriented substrate - in contrast to the flat doping tion in microelectronic circuits in which the doping is decanalized.
  • the radiation damage produced and its healing or at increased substrate temperature by diffusion can favor the penetration of the dopants into the depth of the substrate.
  • ion energy the dose called ion fluence
  • focusing of the ion beam multiple implantations at selected energy and dose values and, as mentioned, beam deflections and mechanical relative movements of the semiconductor substrate and the arrays are also possible.
  • the variation of the energy and the dose makes it possible to adapt the doping and modification profile to be generated to the actual application problem.
  • a variation of the energy can also occur during ion irradiation.
  • the aforementioned process of thermal aftertreatment additionally supports the optimization of a generated modification or implantation profile by thermal diffusion and thus an optimization of the generated doped semiconductor substrate, in particular the solar cell parameters that can be achieved in the process.
  • the doping profiles can thus be adapted specifically and with almost any freedom to the requirements of the semiconductor substrate to be produced.
  • Fig. 5 shows schematically the simplest construction for an exemplary
  • Micro-ion emitter with a source of ions 4 needle or capillary type in conjunction with an aperture 15 in the embodiment shown here projects into the I onenánnreservoir 4 a tip 12.
  • the tip 12 is associated with an extractor 13.
  • the components 12 and 13 are at different electrical potentials.
  • an ionic current is generated from the tip 12 in the direction of the Exraktorblende 13, wherein the ions tion by an extractor 14 leave the ion source.
  • a downstream aperture diaphragm 15, which may consist of an electrically inert material or is at the same potential as the extractor diaphragm 13, is used for beam shaping and produces a more or less wide beam spot 16 with a more or less laterally extended implantation region 2a on the semiconductor substrate 2.
  • the electrical potentials of the extractor diaphragm 13 and the aperture diaphragm 15 can also be selected so that the ions have a higher or lower energy after leaving the aperture diaphragm than after leaving the extractor diaphragm.
  • FIG. 6 shows, as a development of the example shown in FIG. 5, a micro-ion emitter with a needle or capillary type ion source with an aperture stop and an ion optic.
  • the construction of the ion source corresponds to the embodiment of FIG. 5.
  • an ion optics in the form of the already mentioned electrostatic lens 6 is interposed between the ion source and the aperture diaphragm 15. This is designed so that the ion source and in particular the extractor aperture with the extractor opening 14 is at the focal point of the ion optics.
  • a parallel ion beam is generated or at least the electrostatically induced beam expansion within the ion beam is sustainably suppressed.
  • the beam can not only be formed in parallel, but also focused on the semiconductor substrate.
  • the beam spot 16 on the semiconductor substrate 2 is thereby smaller and more focused. This allows the reduction of the single structure. It is also possible the Defocus beam to the beam, z. As in the transport Wafert almost hide.
  • FIG. 7 shows a micro-ion emitter with a needle-type ion source according to the exemplary embodiments from FIGS. 5 and 6 with an additional ion optics 17 and the post-acceleration unit 7 already mentioned.
  • the aperture diaphragm 15 is supplemented by the ion optics 17, while FIG the post-acceleration unit 7 influences the energy of the ion beam and thus, as described, determines the penetration depth of the ions in the beam spot 16 on the semiconductor substrate.
  • Fig. 7a shows a micro-ion radiator with an inserted ExB filter 17a for mass separation.
  • the rest of the construction corresponds to the construction according to the embodiment from FIG. 7.
  • the ExB filter it is possible to eliminate ions from the ion beam and thus to improve the purity of the beam.
  • FIG. 8 shows a modification profile which can be generated by way of example using the example of a doping for a PERL solar cell in a cross-sectional representation.
  • the solar cell consists of a silicon wafer 18 which has a base doping, for example an n-type doping.
  • On the back of the wafer are local dopants 19.
  • the local dopants are, for example, p + doped.
  • the lateral extent of the local dopants and their depth can be predetermined in the manner previously described and are accessible to process control.
  • a front end doping 20 is provided. This covers the front of the wafer substantially completely and over a large area. For example, it has an n + doping.
  • a doping structure can be achieved by a wide aperture and a low focusing of the ion beam in conjunction with a movement of the wafer or the array of the microionic ion. reach strahier, where it comes to the overlap of individual beam spots.
  • the doping structure of the wafer thus formed is supplemented by a front-side contact 21 and a rear-side passivation layer 22.
  • the latter consists, for example, of silicon oxide or aluminum oxide.
  • the remindcostpassivier Mrs is etched in places at individual holes 23, so that a back-side contact 24 passes through the local dopants 19 and electrically contacted.
  • Fig. 9 shows a view of the PERL cell of Fig. 8 on the surface with the local dopants 19.
  • the local dopants 19 have a respective diameter b adjustable by the focusing of the ion beam and are in the form of a square grid with a grid spacing a distributed over the back surface.
  • the lattice spacing a corresponds to a distance of the micro-ion radiators within the two- or one-dimensional implantation array as shown in FIG. 4. This distance can be changed as required.
  • the previously explained diaphragms and electrostatic elements can each be arranged on a grid, a disk or a metal sheet. Also possible is an arrangement which is designed similar to a printing stencil. In such a configuration, the electrostatic potentials of the ion optical elements are equal to each other because they are connected via the same electrically conductive support member.
  • the extractor electrode can be formed as a continuous sheet into which any number of holes are made, each hole being associated with a microionic emitter. ever The size of the sheet can be used to bring in 10,000 and more holes for a corresponding number of micro-ion lamps.
  • the diameter b of the local dopants is set via the control of each individual micro-ion radiator, the "lattice constant" a results either by a direct imaging of the array unit on the semiconductor substrate 18 or by an interaction of the array unit with a feed device of the semiconductor substrate and / or the array unit.
  • the combination with a deflection unit by means of electric fields is also possible
  • the grid spacing is approximately 500 ⁇ m and the diameter b of each individual doping is approximately 50 ⁇ m.
  • the edge length of the resulting solar cell is about 160 mm with an area of about 245 cm 2.
  • the total number of dopants on the wafer reaches a figure of about 100,000.
  • the advantage of using the implantation array is shown in a comparison between the total area of the wafer and the total area of the doped points.
  • the area of a single dopant is about 20 ⁇ 10 -6 cm 2 . At 100,000 doping points, this corresponds to a doped total area of about 2 cm 2 . Therefore, the ratio between the doped total area and the total area of the wafer is found to be 2 cm2 / 245 cm 2, which corresponds to a value of approximately 0.008. This means that about 1% of the area of the wafer is locally doped.
  • an overall current of 50 mA is possible with an array of 1000 micro-ion radiators. If 10000 micro-ion lamps are used, a correspondingly higher total current results to 500 mA. Such a value corresponds to the total flow of about 10 conventional high current implanters.
  • the process time of ion implantation when using the array of the invention shortens to about 1/10 of the process time, which is otherwise to be applied when using the Hochstromimplanters.
  • Another advantage of the implantation method according to the invention is evident in terms of the required implantation time. Of particular importance here is the physical size of an implantation dose D (particle flux). This establishes a relationship between the implant current I, the implantation time t, the ion charge q and the source area F and is by the relationship
  • the required irradiation time T for a semiconductor substrate with a given implantation area F 1, an ion charge q, the implantation current I and the dose D is determined by the relationship
  • T (D ⁇ q ⁇ F,) / I.
  • the implantation area is smaller because in fact only the actual implantation points and not the entire substrate surface are irradiated by the array of microionic radiators.
  • Micro-ionizer can be forced by a factor of 10 with respect to the implantation current.
  • FIG. 10 shows a further exemplarily producible implantation pattern using the example of an I BC solar cell in a plan view.
  • the solar cell consists of a semiconductor substrate 25 with an n + or p + -doping, which occupies 60 to 95%, preferably 80 to 90% of the wafer surface. Furthermore, an undated region 26 is provided, which only has a p or n base doping of the
  • the undoped region occupies about 10 to 0% of the wafer surface.
  • a p + or n + -doped comb region 27 is provided, which has a region 25 opposite to the doping. This area occupies about 40 to 5% of the water surface. It should be noted that the area 26 can also assume a nominal negative share. This is the case when the doping regions 25 and 27 overlap. From the figure it can be seen that the described areas form an interlocking comb-like structure.
  • the surface thus doped has a spacing dimension c of the doping region 27 called "pitch.” This dimension denotes, for example, the distance of ion beams of a one-dimensional array
  • the undoped region has a width d.
  • the width d moves in a range from 0 to about 200 ⁇ m.
  • the width e of each individual comb is present here Example about 800 ⁇ , the length f of the comb structure is many times greater. It is about 10 mm to 160 mm or more.
  • FIG. 11 shows a detail of an I BC solar cell with an ion implantation array in a view from above, with a representation of the fabrication carried out in the process and of the array used in the process.
  • the implantation array 10 in this case consists of line-arrayed micro-ion radiators 1, which are fastened and guided in a strip-shaped holder 28.
  • the comb structure to be doped on the semiconductor substrate according to FIG. 10 is now produced in such a way that the line-like array is first moved to a predetermined position over the semiconductor substrate and positioned there. Of course, this relative movement can also be realized via a corresponding movement of the semiconductor substrate by means of a displacement device.
  • the microionic emitters of the array are simultaneously activated and each deposit an ion current onto the semiconductor substrate.
  • FIG. 12 shows an exemplary bulk separator in the form of an ExB filter in a top view.
  • an ion optics is provided.
  • This comprises a first magnetic plate 33 and a second magnetic plate 34. These are each designed as a magnetic north pole and a magnetic south pole.
  • a plate capacitor unit is present. This consists of a series of capacitor plates 35, which are held by means of insulators and brackets 36 from each other at a distance.
  • the magnetic plates 33 and 34 are part of a surrounding magnetic yoke 37.
  • the magnetic yoke may be formed as a permanent magnet. In the present example, the magnetization takes place via a
  • Magnetic coil 38 Superconducting magnets and coil arrangements can also be used to increase the field strength.
  • the entire arrangement of the ExB filter is powered by a control unit with power supply 39 with control pulses and electrical power.
  • An ExB filter is a velocity filter or mass filter for ions in which a selection of the ions is carried out by a crossed electric and magnetic field.
  • the field vectors of the B field generated by the magnetic disks are perpendicular to those of the E field between the capacitor plates.
  • the entire arrangement realizes the known from mass spectrometry mass separation, which should not be shown here in detail. It is important that over the voltages applied to the plate capacitors, the electric field strength within the capacitors and a change in the current flow in the magnetic coil 38, the magnetic field prevailing between the magnetic plates can be changed. This requires one each from the ion masses dependent trajectory of the ions present in the ion beam.
  • the ions can thereby be selected for their mass. In particular, it is thereby possible to separate out the ions which are still present in the mixture in the eutectic melt of the ion source and intended for ion modification, and to direct them to the semiconductor substrate.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Physical Vapour Deposition (AREA)
  • Photovoltaic Devices (AREA)
  • Physical Deposition Of Substances That Are Components Of Semiconductor Devices (AREA)

Abstract

L'invention concerne un dispositif pour la modification d'un substrat semiconducteur par faisceau d'ions ou par implantation ionique, avec au moins une microsource d'ions composée d'au moins un agencement à émission de champ produisant un faisceau d'ions focalisable, orienté vers le substrat semiconducteur, composé d'un émetteur d'ions avec un réservoir d'ions à un premier potentiel électrique, un extracteur et/ou une lentille électrostatique à un deuxième potentiel électrique et une unité de post-accélération à un troisième potentiel électrique. Dans le procédé, le substrat semiconducteur est soumis à des faisceaux d'ions orientés provenant d'un réseau d'implantation composé de microsources d'ions à émission de champ et, grâce à une réponse pilotée des microsources d'ions à émission de champ, produit dans le substrat semiconducteur un profil de modification qui dépend du lieu dans son extension latérale et/ou dans sa profondeur.
EP10790430A 2009-12-11 2010-12-10 Dispositif et procédé de modification d'un substrat semiconducteur par un faisceau d'ions Withdrawn EP2510534A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102009057970 2009-12-11
PCT/EP2010/069383 WO2011070156A2 (fr) 2009-12-11 2010-12-10 Dispositif et procédé de modification d'un substrat semiconducteur par un faisceau d'ions

Publications (1)

Publication Number Publication Date
EP2510534A2 true EP2510534A2 (fr) 2012-10-17

Family

ID=43709165

Family Applications (1)

Application Number Title Priority Date Filing Date
EP10790430A Withdrawn EP2510534A2 (fr) 2009-12-11 2010-12-10 Dispositif et procédé de modification d'un substrat semiconducteur par un faisceau d'ions

Country Status (2)

Country Link
EP (1) EP2510534A2 (fr)
WO (1) WO2011070156A2 (fr)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8697559B2 (en) 2011-07-07 2014-04-15 Varian Semiconductor Equipment Associates, Inc. Use of ion beam tails to manufacture a workpiece
CN110851939A (zh) * 2018-07-27 2020-02-28 核工业西南物理研究院 圆柱形阳极层霍尔推力器寿命评估的仿真计算方法

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4892752A (en) * 1987-08-12 1990-01-09 Oki Electric Industry Co., Ltd. Method of ion implantation
US4902898A (en) * 1988-04-26 1990-02-20 Microelectronics Center Of North Carolina Wand optics column and associated array wand and charged particle source
WO2001059805A1 (fr) * 2000-02-09 2001-08-16 Fei Company Faisceau d'ions focalise multi-colonnes pour applications de nanofabrication
GB2374979A (en) * 2000-12-28 2002-10-30 Ims Ionen Mikrofab Syst A field ionisation source
KR20030095313A (ko) * 2002-06-07 2003-12-18 후지 샤신 필름 가부시기가이샤 레이저 어닐링장치 및 레이저 박막형성장치
EP1622182B1 (fr) * 2004-07-28 2007-03-21 ICT Integrated Circuit Testing Gesellschaft für Halbleiterprüftechnik mbH Emetteur pour source de ions et procédé pour sa production
CN101248505B (zh) * 2005-07-08 2010-12-15 耐克斯金思美控股公司 受控粒子束制造用的设备和方法
EP2054938A2 (fr) * 2006-07-07 2009-05-06 Sri International Mouillage de métal liquide de structures d'émission de particules chargées micro-fabriquées
JP4205122B2 (ja) * 2006-07-19 2009-01-07 株式会社日立ハイテクノロジーズ 荷電粒子線加工装置
EP1956630A1 (fr) * 2007-02-06 2008-08-13 ICT Integrated Circuit Testing Gesellschaft für Halbleiterprüftechnik mbH Séparateur de masse achromatique
DE102008064781B3 (de) * 2007-04-23 2016-01-07 Hitachi High-Technologies Corporation lonenstrahlbearbeitungs-/Betrachtungsvorrichtung

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
L.A. GIANUZZI, FA. STEVIE: "Introduction to Focused Ion Beams", 2004, SPRINGER, ISBN: 0-387-23116-1 *

Also Published As

Publication number Publication date
WO2011070156A3 (fr) 2011-09-09
WO2011070156A2 (fr) 2011-06-16

Similar Documents

Publication Publication Date Title
DE2412102C2 (de) Verfahren und Vorrichtung zum Herstellen einer dotierten Halbleiterzone und einer ohmschen Kontaktdoppelschicht hierauf
DE60014461T2 (de) Feld Emissions Vorrichtung mit ausgerichteten und verkürzten Kohlenstoffnanoröhren und Herstellungsverfahren
DE102011006899B4 (de) Verfahren zur Herstellung von Kontaktelementen durch mechanisches Aufbringen von Materialschicht mit hoher Auflösung sowie Kontaktelement und eine Vorrichtung zur Herstellung
DE102010025967B4 (de) Verfahren zur Erzeugung einer Vielzahl von Löchern, Vorrichtung hierzu und Glas-Interposer
DE60113245T2 (de) Elektronenemissionsapparat
DE69830664T2 (de) Vorrichtung zum emittieren eines geladenen teilchenstrahls
DE69025831T2 (de) Elektronemittierende Vorrichtung; Herstellungsverfahren Elektronemittierende Vorrichtung, Herstellungsverfahren derselben und Anzeigegerät und Elektronstrahl- Schreibvorrichtung, welche diese Vorrichtung verwendet.
EP0002472B1 (fr) Dispositif et procédé pour le dépôt de couches matériau semiconducteur dopé sur la surface d'un substrat semiconducteur
DE112010002551T5 (de) Geladene teilchen abstrahlende vorrichtung
DE1053691B (de) Verfahren und Einrichtung zur Materialbearbeitung mittels Ladungstraegerstrahl
EP0725843A1 (fr) Procede et systeme de vaporisation par bombardement electronique active au plasma
DE102010060910A1 (de) Verfahren und Vorrichtung zur Ionenimplantation
DE2335821A1 (de) Teilchenbeschleuniger
DE102021114934B4 (de) Verfahren zum analytischen Vermessen von Probenmaterial auf einem Probenträger
DE3114644A1 (de) Verfahren und vorrichtung zur erzeugung von elektronenimpulsen hoher dichte
DE19634193C2 (de) Feldemissionsvorrichtung
EP2510534A2 (fr) Dispositif et procédé de modification d'un substrat semiconducteur par un faisceau d'ions
EP3970180B1 (fr) Dispositif et procédé d'implantation de particules dans un substrat
DE102010024543A1 (de) Verfahren und Vorrichtung zum Beschichten einer Oberfläche
DE4416597A1 (de) Verfahren und Vorrichtung zur Herstellung der Bildpunkt-Strahlungsquellen für flache Farb-Bildschirme
DE102023133567A1 (de) Verfahren zum Herstellen einer Mikrooptik für ein Vielzahl-Teilchenstrahlsystem, Mikrooptik und Vielzahl-Teilchenstrahlsystem
DE3511141C2 (fr)
JP2001015059A (ja) 高精細シングルイオン抽出方法及び該方法を適用した高精細シングルイオン注入装置及び方法
DE19802779A1 (de) Elektronenemittervorrichtung
DE102009005620B4 (de) Verfahren und Anordnung zur Erzeugung eines Elektronenstrahls

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20120711

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DAX Request for extension of the european patent (deleted)
17Q First examination report despatched

Effective date: 20130924

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20140405