TWI355371B - Coloured diamond - Google Patents

Description

1355371 BRIEF DESCRIPTION OF THE INVENTION The present invention relates to a method for producing colored diamonds, particularly relating to, for example, colored single crystal chemical vapor deposition suitable for decorative purposes (hereinafter referred to as CVD). )diamond. C Prior Art Background of the Invention True diamonds have an indirect band gap of 5.5 eV and are transparent in the visible portion 10 of the spectrum. A defect or color center (hereinafter referred to as a color center) having an associated energy level within the band gap is introduced, resulting in a unique color of the diamond, which is determined by the type and concentration of the color center. This color is derived from light absorption or illumination or a combination of both. An example of a common color center that exists in synthetic diamonds is nitrogen. When nitrogen is in a neutral charge state at a replaceable lattice position, nitrogen 15 has a relative energy level lower than the conduction band by about 1.7 eV, resulting in absorbance, giving the diamond a characteristic yellow. brown. It is well known that the post-growth treatment of diamonds, for example, by irradiation with sufficiently excited particles or radiation (electrons, neutrons, gamma rays), can produce lattice defects (cracks and voids), which are then appropriately annealed, resulting in the formation of a color center (eg nitrogen). 20 Blank [NV] color center) gives the diamond the desired color (see, for example, EP 〇 615 954 A EP 0 326 856 A1 and references cited therein). Other characteristics of the color center and details of the man-made manufacturing were discussed by J〇hn Walker in Physics Progress Report No. 42 1979. The manual manufacturing method for forming a color center in these reports includes the following steps: electron beam irradiation on the crystal form 5 1355371 into a lattice defect, and if necessary annealing is performed to allow the crystal of the lattice defect combination crystal to be entrained atom. However, due to the formation of competitive defects and the strong dependence of the growth fan area on the concentration of defects (such as nitrogen) in the diamond, the color and uniformity of manufacture is limited. 5 The color of the diamond colored by the post-growth color center formation method is the color of the rough diamond before post-treatment, combined with the effect of one or more color centers modified or produced during post-growth processing. In order to achieve a predetermined decorative value, a combination of high transparency and predetermined color is achieved, and the usual practice is to use a diamond that is initially colorless or pale yellow. Therefore, this method is not easy to apply to brown 10-color single crystal CVD diamonds. EP 671 482, US 5, 672, 395 and US 5, 451, 430 describe the use of HPHT treatment to densify diamonds to make polycrystalline CVD diamonds more transparent. It is also known that brown natural diamond color can be altered by high pressure and high temperature annealing. For example, a natural Ila type drill can be converted to a colorless color by annealing at a very high temperature under a stable pressure; or a natural Ila type drill can be converted into a peach color by annealing at a relatively low temperature under a stable pressure. The natural brown color is believed to be related to plastic deformation, but the true cause of brownness and how brown is modified by annealing remains unclear. Color has three visual attributes: hue, brightness, and saturation. Hue allows colors to be classified as red, green, blue, yellow, black, or white, or a color attribute that is adjacent to a tone of 20 pairs of basic tones or triplets. White, gray, and black objects vary in lightness to darkness. Brightness is a color attribute defined by a degree similar to a neutral colorless scale. Brightness begins with white, passes through the darker shades of gray, and is finally black. Saturation is a 6 color attribute defined by the degree of difference in colorless colors of equal brightness. Saturation is also a descriptive term for color intensity. The diamond industry uses adjectives that are extremely strong, strong and vivid to represent the different saturations of visual assessment. For the CIE L*a*b color system, the saturation is the degree of deviation from the neutral color axis (defined as saturation = [(a*)2+(b*)2], see below). Brightness is the visual quality that is perceived separately from saturation by 5 degrees.

The method of depositing materials, such as diamonds, onto a substrate by CVD has now been established and is described in detail in the patent and other references. When a diamond is deposited on a substrate, the method generally involves providing a gas mixture that, upon dissociation, provides hydrogen or halogen in atomic form (eg, F, 10 C1), and C or carbon-containing groups and other reactive species such as Chx, CFX where X is 1 to 4 ° In addition, there may be an oxygen source, and there may be a source of nitrogen and a source of boron. Nitrogen can be introduced into the synthetic plasma in a variety of forms; inert gases such as helium, neon or argon are also typically present from N2, NH3, air and various methods. A typical source gas mixture contains a hydrocarbon CxHy (wherein X and y are each 15 1 to 1 Torr) or a halogenated carbon type CxHyHalz (wherein X and z are each 1 to 10, and y is 0 to 10), and the selectivity is as follows One or more: COx (where X is 0.5 to 2), 〇2, %, N2, NH3, B2H6, and an inert gas. Each gas may be present in its natural isotope ratio, or the relative isotope ratio may be manually controlled; for example, hydrogen may be present as ruthenium or osmium, and carbon may be present at 12C or 13C. Dissociation of source gas mixture 20 can be dissociated by energy sources such as microwave, RF (radio frequency) energy, flame, hot filament based or jet based technology; reactive gas species so produced are allowed to deposit on the base A diamond is formed on the material. CVD diamonds can be produced on a variety of substrates. Polycrystalline CVD diamonds or single crystal CVD diamonds can be made depending on the nature of the substrate and the details of the processing chemistry. SUMMARY OF THE INVENTION SUMMARY OF THE INVENTION In accordance with the present invention, a method of making a single crystal CVD diamond having a desired color includes the steps of providing a single crystal CVD diamond that is colored (occasionally the color itself is the desired color). And heat treating the diamond under conditions suitable to produce the desired color. The single crystal CVD diamond used as the starting material is colored, and the heat treatment is carried out under controlled conditions suitable for producing another desired color in the diamond. 10 You can often see multiple colors in one diamond. The primary color is under standard illumination and viewing conditions. If the observer is forced to describe only one color most accurately, the observer will pick the primary color. A diamond having a designated primary color may have a color that is modified via other color ranges of the primary color in a three-dimensional color space such as the CIE L*a*b* color space (described in detail later). Example 15 As in the three-dimensional color space, the peach color line borders the borders of white, gray, brown, orange, purple, and red. Therefore, peach-colored diamonds can in principle display any color as a modified color to an unequal degree, and are suitably described as, for example, gray peach, maroon or orange peach. The invention and the scope of the patent application, when referring to individual colors (e.g., brown diamonds, green diamonds), indicate that the individual colors represent primary colors, and there may be 20 secondary modified colors. Usually the diamond is polished, so the color that looks when viewed in the desired way (upward) is quite different from the characteristic color of the diamond seen when viewed from the side. Part of the reason is that the diamond facets are polished so that when the diamond is viewed in the desired way, the light enters the viewer's eye. The length of the light inside the diamond is one or more times. P reflection is greatly increased. The effect of the increase in the length of the optical path on the color code can be modeled in the manner described later. The color of the single crystal CVD diamond used as the starting material is typically brown. 5 Under appropriate heat treatment conditions, the brown color can be converted into a variety of predetermined colors, including 'colorless and nearly colorless, especially for special colors. "Special grades" 4 The classification of gemstones with more diamonds and more colors and more satisfactory colors can be used to produce special green and extra peach colors in diamonds. Early-crystal CVD diamonds can be in the form of layers or in the form of sheets in the __ layer, for example, cut into gems. The invention is particularly applicable to thick diamond layer thick diamond layers having a thickness greater than 1 mm and for application to the diamond layer. In addition, the CVD diamond layer preferably has a uniform crystal quality in its thickness direction, so that any desired color is not quenched or hidden by any defect in the low crystal quality in any region of the layer. Use this diamond layer or diamond layer to create a special peach color and a special green range in the peach and green range. The nature of this color range cannot be heat treated by known natural diamonds by known methods, or known as HPHT synthetic materials. Know the method to handle the expected color essence. Specially single-crystal CVD diamond layers with a thickness of over a millimeter can be used to make products such as precious stones, both of which have an orthogonal dimension of more than 1 mm. 20 (d) A single crystal CVD diamond added or subtracted or retracted under the conditions of the present invention produces a desired color range. The color range can be defined by a (10) LW color space. It has been found that after the heat treatment, the single crystal CVD diamond has a CIELabb* coordinate for a 1 mm thick parallel layer made of the diamond, and the coordinate system is located in one of the following ranges: 1355371 0<b*<8 0<;b*<40<b*<20<b*<l 5 As explained above, the heat treatment of the single crystal CVD diamond results in a colorless or nearly colorless diamond. Close to colorless diamonds can be defined in CIE L*a*b* color space. Particularly such heat treated diamonds have a saturation (C*) of less than 10 or less than 5 or less than 2 for a 1 mm thick parallel layer made of the diamond. · 10 Heat treatment will vary depending on the nature of the CVD diamond being grown and the desired color desired for the CVD diamond. For example, it has been found that a thick layer of brown single crystal CVD diamond or a small piece cut from the diamond layer can be subjected to a period of time, typically 4 hours, at a temperature ranging from 1600 ° C to 1700 ° C under a stable pressure of the diamond. Anneal to the desired peach to green range. Unexpectedly, 15 the thick layer of diamond and the color of the small piece cut by the diamond layer can also be in the pressure of the graphite stable zone, in the inert atmosphere or stable atmosphere, in the temperature range of 1400 ° C to 1600 ° C The heat treatment is carried out for a period of time, typically 4 hours, and is changed to a peach to green color. An example of an inert atmosphere is argon (Ar). In one form of the invention, a single crystal CVD diamond is produced by a method of mixing nitrogen with a solid diamond to a concentration of 0.05-50 ppm. The lower limit of this range is preferably 0.1 ppm, more preferably 0. 2 ppm and still more preferably 0.3 ppm. The upper limit of this range is preferably 30 ppm, more preferably 20 ppm and still more preferably 10 ppm. For example, it can be achieved by an electropolymerization method in which gas 10 gas is present in the gas phase (initially in the form of N2, NH3 or several other nitrogen-containing molecular forms).

formula). In order to achieve reproducible results and to adjust the final product, the N in the preparation must be controlled. Typical concentrations in the gas phase (all nitrogen phase concentrations in this specification are expressed as equivalents of N2, such as one molecule equivalent to two ΝΉ3 molecules) of 0.5 ppm to 500 ppm, more preferably i ppm_1 〇〇 ppm and more preferably For 2

Ppm-30 ppm, but skilled artisans understand that nitrogen uptake is extremely sensitive to process conditions such as temperature, pressure and gas phase composition, so the invention is not limited to these limits. Different isotopes of nitrogen can be used, such as 14N or 15n. The effects of different isotopes on growth chemistry and final results are usually not significant, but some of the defects formed by N may have their associated optical bands shifted by atomic weight differences. In addition to Example 8, 14N is used to derive the information provided in this specification, but the scope of the invention covers all N isotopes. The uptake of impurities (e.g., nitrogen) is also sensitive to the growth sector, and preferably the final layer is predominantly or substantially entirely a growth sector or a growth region type having a symmetric relationship. Growth sectors such as {100}, {1U}, {11〇}, {111} may be used, and more preferably growth sectors {100} and {113} and optimal growth sectors {100}. Diamonds may additionally contain low concentrations of other dopants such as p, 8 and 8, but preferred methods exclude other dopants. The heat treatment (annealing) is usually carried out at 丨2〇〇-2500. (: The temperature of the range is carried out. The lower limit of such a temperature range is usually set by the treatment required to be lightly annealed to achieve an acceptable kinetic rate setting, in addition to the equilibrium defect concentration set by the selection of the kinetic progression. The upper limit is set by practical considerations because it is difficult to operate the HpHT method above 25 ° C, but an appropriate annealing above this temperature can promote annealing to form a particularly near-colorless diamond. The lower limit of this range is preferably 125 〇. (:, more preferably i3 〇〇 ec and more preferably 1400 ° C. The upper limit of this range is preferably 2 〇〇〇 ° C, more preferably 1900 ° C and still more preferably 1800. The annealing is carried out for a period of 3-3 X 1 〇 6 seconds. The lower limit of the range is preferably 30 seconds, more preferably 100 seconds and more preferably 3 sec seconds. Preferably, it is 3 X 1 〇 5 seconds, more preferably 1 X 1 〇 5 seconds, still more preferably 2 X 104 seconds and more preferably 7 X 1 〇 3 seconds. Annealing can be carried out under stable pressure of the diamond, or for example It can be carried out in an inert atmosphere or a stable atmosphere at or near atmospheric pressure. There is an interdependence between the equal variables, and the annealing time required for lower temperature is longer; or the annealing time is longer when the steady pressure is applied at the same temperature. Such a specific temperature range is suitable for a specific time range, depending on whether or not stable pressure is used, The temperature limit for annealing without diamond-stabilized pressure is usually 1600 ° C, which is particularly problematic when the annealing time is long or the treatment is not carefully controlled. However, it can be achieved without using the diamond to stabilize the pressure. Annealing up to 1800 °c, in the extreme case can reach i 9 〇 (r anneal. For the purposes of this specification, the pressure field can be divided into two areas, that is, the diamond stable area 'commonly known as diamond stable pressure, and graphite Stable zone. The most easily available region in the graphite stabilization zone is the region near atmospheric pressure (1.01 X 105 20 Pa). However, in a controlled gas environment, it is usually quite easy to achieve a lower pressure 'for example, 1 X 1〇2 Pa, 1 X 1 〇 5 Pa, and achieve a higher pressure such as 1.02 X 105 Pa - 5 X 1 〇 5 Pa. The pressure range below $ X 1 〇 5 Pa is usually annealed to defects inside the diamond volume and Unresolved effects. Step-by-step understanding of the pressure from 5 X 105 Pa to the stable pressure of the diamond did not result in any individual defects. The basic properties of this 12 1355371 are the same as those obtained by annealing at or near atmospheric pressure. There is no difference in the basic properties, but for example, the reaction rate may be a function of some smooth pressure between the two extremes, so the balance between defects and the interaction between defects may change to some extent. The method of the present invention is 5 Annealing of the graphite stabilizing zone is typically done at atmospheric pressure for simplicity, but this does not limit the annealing of the process of the present invention to other pressures in the graphite stabilizing zone. Conventional pressures for high pressure presses are expressed in kilobars. For the sake of consistency, all the pressures in this specification are expressed in Pascals. The high-pressure conversion used is converted to Pakistan or kilobars due to the number of 1 bar = 1.Ox 1〇5 Pa. The colored CVD diamond crystal of the present invention preferably has a desired hue. The hue angle of a particular hue can be found by extending the line of the point indicated by the hue on the a*b* color map, as detailed later, and shown in Fig. 4. The hue angle of the CVD diamond after heat treatment is typically less than 65 degrees or less than 60 degrees, or less than 55 15 degrees or less than 50 degrees. Peach-colored diamonds are known to be the most beautiful and rare, and are therefore preferred and priced by jewelers, collectors and consumers (peach diamonds, John M. King et al., Gems and Jewelry, Summer 2002). In the diamond industry, the value of green diamonds is also high and is appreciated by everyone (collection and classification of colored diamonds, Stephen C. Hofer, 1998, Ashland 20 Publishing Company, New York). Usually peach-colored and green diamonds are more expensive than solid-colored diamonds, and secondary-modified colors have a weaker effect. The heat treatment conditions or annealing conditions of the present invention can enhance the color purity by increasing, removing, reducing or modifying the absorption of the color modification. Simultaneous annealing or heat treatment reduces the concentration of defects and reduces the absorption over a wide range of spectra, increasing the brightness by 13 1355371 degrees. Some of the color centers that contribute to the color of brown CVD diamonds are single crystal CVD diamonds, or unique color centers for small pieces cut or fabricated from single crystal CVD diamonds, particularly affecting thick layers of perceived color. It is very different from the color center that contributes to the natural color of the stone. The reason is that the absorption belt caused by the former does not appear in the absorption band of natural diamonds. It is believed that some of the color centers are associated with the extremely localized destruction of diamond bonds within the single crystal CVD diamond. The evidence is derived from Raman scattering observed from non-diamond carbon using an infrared laser source (eg 785 nm or 1064 nm). There are no 10 Raymond scatterings on brown natural diamonds. The relative absorption intensity of the brown single crystal CVD diamond in the absorption band of the visible region of the spectrum can be varied by annealing and simultaneously changing the Raymond spectrum. The temperature at which the absorption spectrum changes is much lower than the temperature required to change the color of the brown natural diamond. Even in the absence of oxygen, at temperatures well below the graphitization of the diamond, such as 1600 ° C or below, a significant color change can still be achieved by annealing at atmospheric pressure in an inert atmosphere. Since the conversion of non-diamond carbon into diamonds usually requires a stable zone of diamonds and is handled under high pressure and high temperature conditions, this finding is unexpected. The relevant characteristics of the CVD diamond growth machine may result in an absorption band taken at about 350 nm and about 510 nm, and an absorption band, which takes 20 in near-infrared light and extends into the red region of the visible spectrum. . The color centers responsible for these absorption bands have a significant impact on the color of the CVD diamond being grown. This color center does not exist in natural diamonds or other synthetic drills. Gemstones polished from CVD diamonds as grown may have desirable colors, including orange-brown and peach-brown. When the diamond is heat treated or annealed under the conditions of the present invention, the relative strength of the absorbent strip 14 1355371 can be altered in a manner that enhances color, such as removal or reduction or increase. The contribution to color change also comes from the formation of a color center through the collapse of a defect such as a diamond produced, or the change in color from the charge transfer process, which changes the main charge state of the defect. Because the annealing step or the heat treatment step can change the combination of color centers to a combination that cannot be produced by the grown CVD diamond, a single crystal CVD diamond having a satisfactory color from a novel color center combination is obtained. As is known to those skilled in the art, a wide absorption band, such as from 350 nm to 510 nm, can vary slightly in maximum strength, but does not change its identity. 10 Schematic diagram 1 is annealed at 2400 ° C for 4 hours at a pressure of approximately 8.0 x 109 Pa (80 kbar), (a) pre-annealed and (b) sample Ex-4 recorded after annealing Ultraviolet-visible absorption spectrum. Figure 2 is annealed at 1900 ° C for about 45 hours at a pressure of about 7.0 x 109 Pa (70 kbar), (a) before annealing and (b) after annealing, the sample Ex-5 is UV- Visible light absorption spectrum. Figure 3 is annealed at 1600 ° C for 4 hours at a pressure of about 6.5 X 109 Pa (65 kbar), (a) before the annealing and (b) after annealing, the sample Ex-6 UV-visible Absorption spectrum. 20 Figure 4 is annealed at 1600 ° C for 4 hours at a pressure of approximately 6.5 X 109 Pa (65 kbar), (a) before annealing and (b) after annealing an ex-violet of sample Ex-6 - The CIELAB a* value and b* value derived from the visible light absorption spectrum are plotted. Figure 5 is annealed at 1600 ° C for 4 hours at a pressure of about 6.5 X 109 Pa (65 kbar), (a) before annealing and (b) after recording the sample Ex-6 violet 15 5 C-implementation of the CIELAB L* value and C* value derived from the light-visible light and the received spectrum]. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 10 The present invention is capable of being converted to another color in a controlled manner under suitable and controlled heat treatment conditions. The CVD diamond (4) is in the form of a thick layer or a small piece cut or manufactured from such a thick layer. The thick single crystal CVD diamond has a high quality f, preferably by providing a diamond substrate, the material having a surface substantially free of crystal defects, extracting a source gas, dissociating the source gas, and allowing the The growth of homogenous epitaxial diamonds is carried out on the surface substantially free of crystal defects. In this way, CVD diamond growth does not contain inclusion bodies, which is a HPH1^ stone formula 1 especially for HPHT diamonds whose color is not dominated by a single substituted nitrogen. 15 Typically the process is carried out in the presence of nitrogen and nitrogen is added to the synthetic plasma. The presence of nitrogen creates a brown colored center in the diamond. When nitrogen is added in a controlled manner, nitrogen completely destroys the growth of the diamond, resulting in a combined color. The center of the color involves carbon bonded in a non-diamond manner, while obtaining a diamond with good single crystal quality. X-ray technology, such as X-ray topology, has good single crystal quality. 20 In order to produce a high crystalline quality, a thick single crystal CVD drill is grown on the surface of a diamond that does not contain crystal defects. In this context, the absence & mainly represents dislocations and microcracks, but the defects also include the boundary of the crystal, the point defects of the N-atoms of the essentially unrelated dopants, the low-angle boundary and any other extension damage to the crystal lattice. . Preferred substrates are low birefringence type natural drill, lb or 11a high pressure/high temperature synthetic drill, or CVD synthetic single crystal 16 1355371 iron. The growth product f on the substrate which is sufficiently free of defects, which grows thicker with the thickness of the layer, the quality deteriorates rapidly, and as the defect structure multiplies, the overall crystal is degraded, twinned, and re-pregnant. The defect density is most easily characterized by optical grading, using, for example, a short electric smear between the cracks described later, after using the optimized plasma or chemical button to reveal the defect (hereinafter referred to as the exposing electricity (10)) The most accurate (iv) optical evaluation determines the defect density. Two types of defects can be revealed: 10 1) Defective quality of the substrate material. For natural diamonds selected, the defect density is less than 50/mm2, with a typical value of square millimeters of milk and other diamonds of 1〇6/mm2 or more. Defects caused by I light, including the poor row structure and microcrack formation, along the trajectory of the polishing line. The defect density can vary considerably from sample to sample, with a typical value of about 102/sq. ft., 5 ή 水 水 to the poor throwing area or 15 of the poorly polished sample being greater than 10/mm 2 . The preferred low density of the defect is (as described above) the defect-related surface lithography density is less than 5 X 1 〇 3 / square mm and more preferably less than 1 〇 2 / mm 2 ; Thus, by carefully preparing the button, the surface of the substrate to be subjected to CVD growth and the content of defects under the surface can be minimized. Included here is 20. Includes any application to materials derived from mining (in the case of natural diamonds) or synthetic (in the case of synthetic materials), as each stage may affect when prepared as a substrate. The density of defects formed inside the material of the plane of the surface of the substrate. Special processing steps include conventional diamond processing such as mechanical mining, tapping and polishing (this is especially best for low-level defects); and non-known techniques such as laser processing or ion implantation and stripping techniques , chemical / mechanical polishing and liquid and electropolymer chemical processing technology. In addition, the surface RQ (measured by the side line of the reticle, the deviation of the root mean square from the plane on the surface side, preferably measuring 0.08 mm length) must be minimized, and the typical value of 5 before any plasma etching is not more than a few nanometers. , that is, less than 10 nm. The specific method of surface damage of the most j-substrate includes in-situ plasma etching - engraved on the growth surface of the homogenous epitaxial diamond. In principle, this etching does not have to be carried out in the original 4 or immediately before the growth, but if the surname is in situ, the maximum effect can be obtained, because the risk of physical damage or chemical contamination of the 10 steps can be avoided. When the growth process is also dominated by electricity, it is usually most convenient to etch in situ. Plasma etching can use conditions similar to the deposition process or the diamond growth process, but there is no carbon source gas present, and typically at a slightly lower temperature, the etch rate is better controlled. For example, the electropolymerization _ condition consists of the following -S multiple conditions: 15 (i) The oxygen residue is mainly hydrogen, selectively containing a small amount of argon and requires small stem oxygen. Typical oxygen etching conditions are 50-450 X 102 Pa pressure, the gas engraved gas contains 1 to 4% oxygen content, 〇 to 3〇% chlorine content and the difference is nitrogen, all percentage φ ratio is expressed by volume 'substrate temperature It is 600-1100. (: (more typically 800 °C), and typical time is 3-60 minutes. 20 (ϋ) Hydrogen name is similar (丨), but there is no oxygen. (m) Another etching method is not based solely on argon. It is also possible to use hydrogen and oxygen, for example, by using a halogen 'other erotic gas or a residual method of nitrogen. A typical engraving is an oxygen engraving' followed by a chlorine engraving, and then a human carbon synthesis time is introduced via the introduction of the carbon body ml/ The temperature is selected such that the other surface damage caused by the treatment can be removed, in order to remove any surface contaminants, but does not form a roughened surface 'and does not follow the extended defects (such as the difference), the defect is It is especially important to make a small pit with a surface because of the etch. Because of the intense etching, it is particularly important that at this stage, the design of the reaction chamber 5 and the composition of the materials must be such that no material is transferred from the plasma. To the gas phase, or to the surface of the substrate. Hydrogen etching after oxygen etching is less specific to crystal defects, rounding the edges and corners caused by oxygen etching of aggressive attack defects, and providing smoother and better subsequent growth. Surface. CVD The surface of the stone-grown diamond substrate is preferably {1〇〇}, ίο (110丨, {113丨 or U11} surface. Due to processing limitations, the actual sample surface directionality can differ from its ideal directionality by 5 degrees, some In the case of up to 1 degree, but less preferred, a difference of up to 1 degree may adversely affect reproducibility. Importantly, in the method of the present invention, the content of impurities for CVD growth must be appropriately controlled. In an atmosphere, I5 or gas is substantially free of any contaminants other than deliberately added nitrogen or other dopants. Nitrogen; the elongation must be controlled to be greater than 500 ppm (expressed as the molecular component of the total gas volume) or 5% of the gas phase target concentration (depending on which is larger); or preferably greater than 300 ppm (expressed as the molecular component of the total gas volume) or 3 °/ of the gas phase target concentration (depending on which is larger); More preferably greater than 1 〇〇 ppm (expressed as the molecular component of the total gas volume of 20) or 1% of the gas phase target concentration (as determined by the larger one). Measured in the gas phase by measuring the absolute nitrogen concentration in the gas phase at a concentration as low as 100 ppb Relative nitrogen concentration needs to be complexed Miscellaneous monitoring equipment, for example, can be achieved by gas chromatography. An example of this method is now described. Standard gas chromatography (GC) consists of: using a narrow bore sample line, by sensing 19 1355371, extracting gas samples Flow, optimized to obtain maximum flow rate and minimum ineffective volume 'passed through the GC sample coil and then sent to waste. The Gc sample coil is -&the coiled tube' has a gj-defined and known volume (typically for standard atmospheric pressure / The main input coil is 1 cubic centimeter), and the sink sample coil can be switched to the carrier gas (high purity helium) line at the position of the sample line 5, feeding the intake phase chromatography column. This will have a known volume. The gas sample is placed in the gas stream entering the column; the process is referred to as a sample injection by the industry. The left-injected sample is carried by a carrier gas through a GC-column (filled with a molecular sieve optimized for the separation of pure inorganic gases), and is partially separated, but a gas of 10 冋/min (such as hydrogen, Argon gas causes saturation of the column, and saturation of the column causes difficulty in separation of, for example, nitrogen. Then the relevant section of the effluent stream from the first column is switched into the feed of the second column, thus avoiding most of the other gases entering the second column, preventing saturation of the column, and thus completely separating the target gas (nitrogen gas) ). This procedure is called "heart distillation." 15 The output of the second column passes through the Discharge Free Detector (DID), and the DID detects an increase in leakage current through the carrier gas due to the presence of a sample. The chemical structure is identified by the gas residence time. The gas residence time is calibrated by the standard gas mixture. The DID reacts more than 5 times in a linear range and is calibrated using a specially calibrated gas mixture containing the species to be detected. Typical weight analysis is in the range of 1〇-1〇〇Ppm and then supplied Confirmed by the business. The linearity of the DID can be confirmed by careful dilution experiments. Target nitrogenous species include gas classes used as deliberate dopants (eg, N2, NH3); and N2' from any air pollution may be related to measurement conditions. 20 1355371 This known gas chromatography is further modified and developed for use in this application, as follows: The method of analysis here is typically performed at 50_500 χ 1〇2 Pa. Normal gas chromatography operations use source gas pressures greater than atmospheric pressure to propel gas through the sample line. Here, the sample is propelled in a way that the waste 5 of the pipeline is connected to a vacuum pump, and the sample is drawn through the pipeline at subatmospheric pressure. When the gas flows, the line impedance can cause significant pressure drop in the line, affecting calibration and sensitivity. Therefore, a valve is provided between the sample coil and the vacuum pump. The valve is closed for a short period of time before the sample is injected to ensure the pressure of the sample coil is stable, and the pressure is measured by a pressure gauge. To ensure that a sufficient amount of sample gas 10 is injected, the sample coil volume is enlarged to approximately 5 cubic centimeters. Based on the design of the sample line, this technology can still operate effectively at pressures as low as approximately 70xl〇2 Pa. The calibration of the gas chromatograph is based on the quality of the injected sample, and the gas chromatograph is calibrated using the same sample pressure as the source of the analysis, for maximum accuracy. The high standard vacuum and gas treatment 15 specifications must be observed to ensure that the measurements are correct. The sampling point can be located upstream of the synthesis chamber to determine the characteristics of the input gas; to determine the indoor environmental characteristics in the synthesis chamber; or to be located downstream of the synthesis chamber. The source gas can be any source gas known to the industry that will contain carbonaceous materials and dissociate the carbonaceous material to produce free radicals or other reactive species. The 20 gas concentrate typically also contains a gas suitable for providing chlorine or dentate in atomic form. The dissociation of the source gas is preferred to the reactor examples known in the art and is carried out using microwaves. However, the transfer of any impurities from the reactor must be minimized. The microwave system is used to ensure that the electrical damage is away from the entire surface, except for the surface of the substrate that is intended to be a diamond 21 21355371 and its mounting surface. Preferred mounting materials are, for example, key, tungsten, broken and carbonized. The preferred reaction chamber materials are, for example, no steel, slag, copper, gold and the beginning. High plasma power density must be used, which is derived from 5 high microwave power (typically used for 25-300 mm substrate diameter of 36 kW) and high gas pressure (50-500 X 1 〇 2 Pa) And preferably 1〇〇χ 45〇2 Pa). • Using the above conditions, a thick layer of brown high quality single crystal CVD diamond can be produced by adding an atmosphere of H5 〇〇 ppm to the gas stream. The high quality single crystal CVD diamond thick layer or its small pieces are then subjected to addition and subtraction. The small pieces may for example be in the form of stones. Specific embodiments of the invention are now described. The following table (9) shows seven different combinations of absorption bands as shown by the grown brown single crystal CVD diamond (labeled as Cases 1-7). The details of the spectral decomposition of brown CVD diamonds into such absorption bands are discussed in WO 03/052177 A1. 15 In each case there is a feature of 270 nm, which is related to the gas impurities in the diamond lattice replacement position. It is well known that the absorption is extended in the visible region of the absorption spectrum to obtain a unique yellow tone of the diamond. · Case 1: The slope feature indicates an increase in the approximate absorption from red to ultraviolet light. This feature can be found in a variety of single crystal CVD diamond layer spectra that are themselves incompatible, or combined with individual substituted nitrogen to produce a matt brown tone. Case 2: Believe in the wide band of about 35 〇 nano and M 〇 nano

Partial destruction of the CVD diamond structure results in a fresh gap state. In the case of single crystal CVD diamond growth samples, these features are combined to obtain a color tone ranging from orange-brown to peach-brown depending on the relative intensity of the three 22 1355371 color contributions. Case 3: The brown single crystal CVD diamond also shows a wide frequency band, taken in the leg region of the spectrum. When ___, the band's length is reduced to visible light, and the red end produces significant absorption. It will itself produce a blue hue. When combined with nitrogen-based viewing, the absorption formed at both ends of the spectrum gives the diamond a green tint. Case 4: The multi-layer brown single crystal CVD diamond layer can be reconfigured as a sum of individual replacement nitrogen, ramp and 350/510 nm bands. This combination gives an orange-brown hue. 10 Cases 5, 6 and 7 cover other combinations of absorption features discussed above. Depending on the relative intensities of the various composition absorption characteristics, these combinations can be obtained in different shades of a range. Table 1 270 nm slope 350 nm 51 〇 nano NIR Lai case 1 Whether or not - no no rii 忖 无 无 褐 案例 2 Case 2 Whether it is peach brown case 3 Whether it is green or not 4 is orange or not Brown Case 5 Whether it is brown Case 6 Whether it is brown Case 7 It is a brown-brown single crystal CVD diamond that is annealed under various conditions to observe its effect. The slope and the 3 50 nm band were found to be substantially removed by the following treatment, which was treated at 1400-1600 ° C for 4 hours under an inert atmosphere of ambient pressure. A similar effect can be achieved by annealing at 16〇〇_i7〇〇°c for 4 hours due to the stable pressure of the diamond. These treatments themselves have a significant effect on the color of the diamond, for example, in Cases 1, 2, 4, 5, 6 and 7 shown in Table 2. Table 2 Initial color final color case 1 Matte brown light brown / close to colorless case 2 peach brown peach to brown peach case 4 orange brown peach brown to brown peach case 5 brown green case 6 brown light brown case 7 brown light brown The temperature range is significantly increased with respect to the negatively charged nitrogen-blank center (with zero phonon line at 637 nm). The increase in absorption (spikes at about 550 nm) tends to make the sample appear peachy. This increase in absorption can be caused by a change in charge transfer that causes more nitrogen-blank centers to be negatively charged. The increase in absorption can be dissociated by vacancies or more complex defects captured by individual nitrogen releases, resulting in an additional nitrogen-blank center. It is also possible to increase the luminescence of the negatively charged nitrogen-blank center excitation, which in extreme cases affects the appearance color of the diamond. Thus, by selecting appropriate heat treatment conditions, a colored single crystal CVD diamond having a peach-to-green color can be produced. It was found that under diamond stable pressure conditions, it was annealed at 1800 °C for 4 hours to make a slight drop in the 510 nm band and the NIR band. The color change shown in Table 3 was produced in the case considered. 24 1355371 Table 3 Initial color final color case 1 Matte brown close to colorless case 2 Peach brown peach to brown peach case 3 Green light green case 4 Orange brown peach case 5 Brown green case 6 Brown light brown case 7 Brown light brown found Under the stable pressure of diamond, annealing at 1900 ° C or higher for 4 hours, the 510 nm band and the NIR band can be removed, and the color change shown in Table 4 is obtained in the case considered. 5 Table 4 Initial color final color case 1 Matte brown close to colorless case 2 Peach brown close to colorless case 3 Green close to colorless case 4 Orange brown close to colorless case 5 Brown close to colorless case 6 Brown close to colorless case 7 'Brown close to colorless Under annealing conditions, the nitrogen-blank center can be dissociated into individual substituted nitrogen and a blank that migrates away from the nitrogen. Therefore, after annealing at this or higher temperatures, the nitrogen-blank center is less likely to affect the (previously brown) diamond jersey. After this treatment, the diamond does show strong green light, 10 so it does give the diamond a green tone under certain viewing conditions and lighting conditions. When excited by 325 nm HeCd laser light, it has already ignited 25 1355371 fire at a high temperature, thus substantially dissociating the nitrogen-blank defect formed during the growth process. The luminescence spectrum of the brown CVD diamond tends to be 450 nm from the spectral region. The advantage of the 550 nm band. H3 luminescence was observed (zero-photon line at 503 nm); after annealing at the highest temperature, N3 luminescence was also detected (zero-photon line at 415 5 nm). Using the aforementioned band gap ultraviolet light or electron beam excitation, the dominant visible light has a tendency to turn from green to blue as the annealing time of the highest temperature annealing is increased. The single crystal CVD diamond spectrum that has been annealed (previously brown) has other illuminating lines. For example, a line of about 851 nm has been excited by a 785 nm laser. Although not shown by a brown CVD diamond such as growth, this illuminating line was observed for a brown CVD diamond annealed at a temperature of 10 to 12 °C. This illuminating line is not found in other diamond types and is therefore unique to brown CVD diamonds that are annealed under conditions that can change color. Other illuminating lines were observed at 1263 nm, 1274 nm, and 1281 nm using Nd:YAG laser excitation (1064 nm). The illuminating line was also observed only for the single crystal brown CVD diamond which had been annealed under the color condition of the changeable color. The color can be significantly improved by annealing, such as the grown brown single crystal CVD diamond, which is shown in the infrared light absorption band associated with the carbon/hydrogen bond stretching mode in the region of 2800-3000 cm. These bands are usually Change, but not completely removed by the annealing process, usually not found in the absorption spectrum of natural or HPHT synthetic diamonds. Some natural diamonds show a hydrogen-related absorption line at 31〇7 cm-1, which is not found in Untreated CVD diamond spectrum. Brown single crystal CVD diamond is annealed at temperatures above about 1800t, resulting in the formation of H-related defects at the absorption line of 3107 cm·ι. This defect is extremely stable and can be found in very high temperature annealed samples 26 1355371 light. 如此. Thus known as CVD material observed 3107 cm.1, indicating the material; the bucket has been annealed according to the hairpin method. In addition, the 3 (1) 7 cm" absorption line combination (10) is observed, especially indicating that the diamond is CVD diamonds, which have been subjected to post-growth high temperature annealing treatment in the manner described herein to change color. In addition to any modifications that can produce color, the aforementioned optical features are for the diamond sample to be used for the first time. (4) The skilled person understands whether or not there is an optical feature presented in this specification. For polycrystalline cvd drills; ε, the gap may create a shorter wavelength of light transmission 10 minus J. The single crystal CVD diamond of the present invention does not contain voids before or after annealing. This diamond sample has been closely studied and included in the profile and plan using a high magnification (1GGG) optical luminescence study. There is no (4) observation of the gap. Therefore, the optical microscope limits the upper limit of the void size to about 2 nanometers. Transmission electron microscopy (TEM) allows thin sections of diamonds to be viewed at a resolution of 15 inches. TEM sections of several unannealed brown CVD diamonds were imaged using TEM to investigate the presence of color due to extended defects. In order to produce a uniform color, such defects need to be thoroughly dispersed in the diamond and have a significant density, so that TEM measurement can be used. This kind of distribution is obviously different from the distribution of the poor or poorly arranged bundles observed by techniques such as Twilight Topography. The difference 20 lines are in the growth direction, and the difference line is from the substrate defect, or from the defect. Particles or other surface defects used in CVD growth. Imaging of hundreds of square micrometers of unannealed brown CVD diamonds did not show any image corresponding to the void. Only the extremely dark brown diamond samples can be found in the form of differential rows and extended defects in the form of laminar defects. For the sample of weak brown or medium brown diamonds, this extension defect was not observed in the study area by 27 1355371 TEM. The color scale can be used as a measure or means for describing the difference between the color of a single crystal CVD diamond produced by the method of the present invention compared to the color of other types or other forms of diamond. 5 The observed color is extremely important for the annealed or heat treated single crystal diamond of the present invention, and because the color code and the observed color are more directly related to the transmission spectrum, the color mark is used to assist in displaying the novel characteristics of the diamond. . The difference in absorption spectra of the CVD diamonds of the present invention results in an observed color that is different from the color previously verified for other CVD diamonds or enamel synthetic diamonds. It's true that beauty is different from person to person, and the color tone may be just a matter of personal preference. On the other hand, the diamond industry recognizes that peach and green diamonds are more expensive than brown diamonds and that the price is higher as the effect of the modified color is reduced. If the gemstones that have been skillfully polished have a high brightness with a specified saturation, the peach or green diamond 15 can produce a satisfactory color. Polished diamonds with the same hue and saturation are less likely to produce satisfactory color if they have low brightness. In addition, the optical window and the electromagnetic transmission application require a certain absorption characteristic. This absorbance characteristic may simply be low total absorbance, or low absorbance in a certain frequency band, or a specific absorption tip 20 peak for use in measuring calorimeter radiation applications. The diamond of the invention is thus particularly useful for optical applications. Optical applications are not limited to visible light, but can also be applied to ultraviolet light as well as to infrared and infrared light. It is specifically contemplated that such materials can be applied to the microwave region. The color of the CIE L*a*b color-coded object is determined by the light transmission/absorption spectrum of the object according to the spectral power distribution of the illumination source and the observed response curve of the eye. The CIE L*a*b color code cited in this patent is derived in the manner described herein. Use standard D65 luminescence spectrum and eye standard (red, green and blue) response curves (G. Wyszecki and WS Stiles, about power, New York 5 - London-Sydney, 1967), CIEL*a*b of diamond parallel side panels The color scale is derived from its transmission spectrum using the following relationship, ranging from 350 nm to 800 nm, data interval 1 nm: transmittance at wavelength λ 1 > λ = spectral power distribution of luminescence 1 〇Χ λ = eyes Red reaction function Υλ=green response function of the eye ζλ=blue response function of the eye Χ=Σλ[8λχλίλ]/Υ〇Υ= Σ x[SkYkLk]/Y〇15 Z= Σ x[Sx.zx.L^] /Y〇 where Y〇= Σ λΥλ.Ιλ L* = 116(Y/Y0)1/3 - 16=brightness (for Y/Y0>0.008856) a*=5O0[(X/Xo)1/ 3-(Y/Yo)1/3] (for X/X〇>0.008856, Y/Y〇> 0.008856) 20 b*=200[(Y/Y〇)1/3-(Z/Z 〇)1/3] (for Z/Z〇> 0.008856) C*=(a*2+b*2)1/2=saturation hab=arctan(b*/a*)=hue angles A modified version of the equation can be used outside of the limits of Y/Y〇, X/X〇, and Z/Z〇. The revised version is shown in the Technical Report of the Commission Internationale de 29 1355371 L’Eclairage Committee (Colorimetric Act (1986)). Usually, the a* and b* coordinates are plotted on the line graph, a* corresponds to the x-axis, and b* corresponds to the y-axis. The positive a* and b* values correspond to the red and yellow components of the hue, respectively. The negative a* and b* values correspond to the green and blue components of the hue, respectively. The positive quadrant of line 5 covers the hue from yellow to orange, and the saturation (C*) is expressed as the distance from the origin. It is predicted how the a*b* coordinate of a diamond with a specified absorption coefficient spectrum changes as the length of the optical path changes. In order to achieve this, the reflection loss is first deducted from the measured absorption spectrum. The scaling is then absorbed by 10 different optical path lengths, and the reaction loss is then added back. The absorption spectrum is then converted to a transmission spectrum which is used to derive a new thickness of CIELAB coordinates. In this way, the dependence of the hue, saturation, and brightness on the length of the optical path can be modeled, and it is determined how the color of the diamond having the specified absorption property per unit thickness is determined by the length of the optical path. 15 L* is the brightness and L* forms the third degree of space in the CIELAB color space. It is important to understand that for diamonds with specific optical absorption properties, the brightness and saturation change with the change in the length of the light path. This can be exemplified in the tone map, where L* is plotted along the y-axis, C* It is plotted along the X axis (for example, Figure 4). The method described in the previous paragraph can also be used to predict how the L*C* coordinates of a diamond with a specified absorption coefficient spectrum 20 are determined by the length of the optical path. The brightness scale can be defined in the following manner: bright: 95 > L* > 65, medium: 65 > L * > 35, dark: 35 > L * > C* (saturation) can be divided into 1〇c* units of saturation range with § explicit terms as follows. 30 1355371 0-10 Weak 10-20 Medium Weak 20-30 Medium 30-40 Medium Strong 40-50 Strong 50-60 Strong - Extremely Strong 60-70 Extremely Strong 70-80+ Extremely Strong Example 1 10 Thick 3.2 mm The CVD layer is grown on a HPHT synthetic diamond substrate. The surface of the substrate to be grown was prepared according to the method described in WO 01/96634. Such a substrate is mounted on a tungsten substrate using high temperature steel welding suitable for use in diamonds. In the microwave reactor, etching and growth cycles are used to prepare the surface of the substrate and then start to grow. More special:

15 1) The reactor was pre-fitted using a spot purifier and the nitrogen concentration of the input gas stream (except for the nitrogen dopant line) was reduced to below 80 ppb as determined by the modified GC method described above. 2) In situ oxygen plasma etching was performed at 235 X 1〇2 Pa and substrate temperature 840 ° C using 3〇8 50/1200 sccm (standard cubic centimeters per second) 〇2/Ar/H2. 20 3) This step was introduced into the 850 Torr hydrogen etch without breaking, with the removal of oxygen from the gas stream. 4) This step moves to the growth stage and is grown by adding a carbon source. The carbon source of this example is 32 seem CH4. The growth temperature at this stage is 980 C ° 5) Nitrogen (N2) is introduced into the growth process at a concentration of 10 ppm. 31 1355371

6) When the growth period is completed, the substrate is removed from the reaction crucible and the cvd layer is released from the substrate. S _ is estimated by the 270 nm absorption characteristic of the absorption spectrum, and the single substituted nitrogen concentration of this layer is estimated to be about 0.40 ppm. The absorption spectrum also contains a broad band taken at approximately 5 360 nm and 520 nm. The absorption coefficient is roughly increased (slope-like elevation of red light to ultraviolet light. The layer is polished to a 0.55 carat round multi-faceted cut diamond The rating is super light brown VS1. It is then annealed at 1700 C for 4 hours at a steady pressure of about 6.5 x 109 Pa (65 kbar). No further treatment is followed by a rating of Super Light Pink Brown VS1. The bottom surface of the round faceted diamond is magnified to record the quantitative absorption spectrum. It indicates that there is no significant change in the concentration of single substituted nitrogen, and the intensity of the 36 〇 nanometer band and the slope of the absorption light s眷 are lower, but The band of approximately 52 〇 nanometers remained approximately unchanged. 15 The absorption spectrum recorded at 77 K showed a weak absorption line from the negative nitrogen-blank center at 637 nm (with associated vibration band). The luminescence spectrum was derived from nitrogen- The luminescence of the blank defect is dominated by the 'zero-phonon line at 575 nm and 637 nm' before annealing and after annealing at 77 K and using 514 nm excitation recording to obtain Raymond's regularized luminescence spectrum' indicating annealing treatment The increase in luminescence from the nitrogen-blank center 20, such an increase in coupling-related absorption, also contributes to the observed change in color. Example 2 Using a method similar to that described in Example 1, a CVD layer having a thickness of 3.1 mm was grown on a HPHT synthetic diamond base. The single-substituted nitrogen concentration of this sample is estimated to be about 0.5 ppm by the characteristic intensity of 270 nm of the absorbance of 32 1355371. The layer is polished to a 0.49-carat round faceted cut diamond, rated as light brown VS1. Annealed at 210 °C for 24 hours at a steady pressure of approximately 7.5 X 109 Pa (65 kbar). After re-polishing to 〇·44 ct, it was rated as a super light gray-green diamond VS1 » then multi-faceted The underside of the cut diamond is magnified and the absorption spectrum is recorded. The absorption spectrum itself is not sufficient to account for the green color of the diamond. The luminescence spectrum (excited with HeCd laser or Xe lamp) shows defects formed by the annealing process (H3 and others) Strong green light with unrecognized defects. In this case, the observed green tone is mainly due to the green luminescence result, and its dependence on the viewing conditions is consistent with this Before the annealing and after annealing at 77 K and using 514 nm excitation recording, the Raymond gauge luminescence spectrum 'indicates the annealing treatment to reduce the luminescence from the nitrogen-blank center', thus facilitating the reduction of the relevant absorption, and also facilitates observation. A change in color. 15 Example 3 A CVD layer of 3.10 mm thickness was grown on a HPHT synthetic diamond substrate in a manner similar to that described in Example 1. The single substituted nitrogen concentration of this sample was determined by the 270 nm characteristic intensity of the absorption spectrum. It is estimated to be about 55 pm. The absorption spectrum also contains a broad band, taking about 360 nm and 515 nm. The absorption coefficient is slightly higher (slope-increasing) from red to ultraviolet. The layer was polished to a 0.51 carat round faceted cut diamond and rated as a premium light brown 13. It is then annealed at 1700 ° C for 24 hours at a steady pressure of about 6.5 x 1 〇 9 Pa (65 kPa). Without any further processing, the diamond was rated as light orange peach 13 ° 33 1355371 and then enlarged to the bottom of the round polyhedral cut vermiculite, and the absorption spectrum was recorded. There was no significant change in the indicated mono-substituted nitrogen concentration. The ramp-up intensity (from red to ultraviolet) in the band intensity and absorption spectrum of Nornami is substantially reduced, but the band around 515 nm remains substantially unchanged. The luminescence spectrum is dominated by the luminescence advantage from the nitrogen 5 blank defect' with a zero phonon line at 5 nanometers and 637 nm. Before and after annealing, 515 nm excitation was used, and the Raymond random luminescence spectrum recorded at 77 Å indicates that the 気4 white luminescence intensity is not greatly affected by the annealing treatment. The observed color change is mainly due to the change in absorption spectrum. 10 Example 4 In a method similar to that described in Example 1, a single crystal CVD diamond was grown to a thickness of 2 mm on a {1〇〇) diamond substrate. The gas mixture included 25 ppm nitrogen. The substrate was taken out to produce a polished CVD sample Εχ-4 of 4.5 mm Χ4·〇_χ2 〇 mm size. 15 Λ The sample is brown. The ultraviolet/visible absorption spectrum is shown as 0 in the first icon. In addition to the single-substituted nitrogen-related absorption characteristics, the spectrum is contained in the broad band of about nm and the secret nanometer. The absorption coefficient is also generally raised toward a shorter φ wavelength. The CVD diamond sample was then annealed at 2400 ° C for 4 hours at a pressure of about 8.0 x 1 〇 9 Pa (8 kPa). The diamond is net colorless after this treatment. Its ultraviolet/visible absorption spectrum is shown as (b) in the second icon. The remaining absorption blended with a lb-type spectral shape containing about 丨1.1 PPm of nitrogen at a single substitution position. Annealing removes the extra absorption exhibited by the sample as grown. The absorption spectrum of this sample was measured before and after annealing, and the CIELAB coordinates of the diamond were derived in the manner discussed in the previous section 34 1355371. The list is as follows. Annealing can reduce b* coordinates and saturation while increasing brightness. Before annealing After annealing a* 2.8 -0.9 b* 12.0 1.9 C* 12.3 2.1 L* 72 86 Example 5

In a manner similar to that described in Example 1, a single crystal CVD diamond was grown to a thickness of 3 mm on a {100} drilled 5 stone substrate. The pressure was 250 X 102 Pa, the substrate temperature was 815 ° C and the gas mixture included 7.5 ppm nitrogen. The substrate was taken out to produce a polished CVD sample Ex-5 of 3 mm X 2 mm x 0.86 mm size. This sample is brown. The ultraviolet/visible absorption spectrum is shown as (a) in the second icon. In addition to the single-substituted nitrogen-related absorption characteristics, the spectrum contains a broad band of about 10 515 nm and 365 nm. The absorption coefficient also generally rises roughly toward shorter wavelengths.

The CVD diamond sample was then annealed at 1900 ° C for 4 hours at a steady pressure of about 7.0 X 109 Pa (70 kbar). The diamond is net colorless after this treatment. The ultraviolet/visible absorption spectrum is shown as (b) in the second icon. The remaining absorbances are reasonably matched to a lb-type spectral shape containing approximately 2.2 ppm nitrogen at a single substitution position. Annealing removes the extra absorption exhibited by the sample as grown. The absorption spectrum of this sample was measured before and after annealing, and the CIELAB coordinates of the diamond were derived in the manner discussed previously. The list is as follows. Annealing can reduce b* coordinates and saturation while increasing brightness. 35 20 1355371 Before annealing After annealing a* 4.6 -0.5 b* 16.8 3.0 C* 17.4 3.0 L* 58.9 87 Example 6

Single crystal CVD diamond was grown to a thickness of 1.8 mm on a {100} diamond substrate in a manner similar to that set forth in Example 1. The pressure was 257 X 102 Pa, the substrate temperature was 5 degrees and the 812<t' gas mixture contained 3.8 ppm nitrogen. The substrate was taken out, and the ultraviolet/visible absorption spectrum of the obtained brown diamond plate E X-6 (not shown as (a) in the third image) was measured.

Then the sample is at 1600. (: Annealed for 4 hours at a steady pressure of about 6.5 X 109 Pa (65 kbar). After this treatment, the dominant component of the color is 10 peach. The UV/Vis absorption spectrum of the sample Ex-6 after annealing is The third icon is shown as (b). The spectrum consists of the absorption of a single substituted nitrogen with a nitrogen concentration of about 1.2 ppm, a band of about 515 nm, and a slight residual absorption in the UV light. Annealing removes The band of approximately 365 nm significantly reduces the absorption of the profile toward shorter wavelengths. 15 Using Renee Shaw with a CCD detector and equipped with an Olympus (01ympus) BH-2 microscope (1〇 objective lens) (Renishaw) Raymond microscope, at room temperature, before annealing and after annealing, recorded the Raymond/luminescence spectrum excited by 785 nm laser. It was found that annealing treatment introduced a series of illuminating lines into the near-infrared region of the spectrum. This includes a 20-absorption line of approximately 851 nm and a broad absorption line of approximately 816 nm and 825 nm. The absorption spectrum of this sample was measured before and after annealing. [1, 36 1355371 Before annealing---if after fire a* 4.0 ------^^4.4 b* 14.5 --4^8 c* 15.0 -^^6.5 L* 72 -----*^81 _____^ __^ Angle adjustment (degrees) 75 -- -47 The method of deriving the CIELAB coordinates of diamonds. The list follows: "The dependence of hue, saturation and brightness on the length of the path is modeled in the way discussed above, and it is understood that the length of the path is different for the diameter of the diamond and The color of the annealed diamond can be achieved. The results are shown in Figures 4 and 5, as the diamonds grown and the annealed diamonds are labeled as follows. Figure 4 spectrum (a) also shows any point on the curve (a* b*) Measurement of hue angle loading f. _ Example 7 Thickness 2.84 mm CVD diamond layer was grown on lb-type HPHT synthetic diamond substrate by the method described in Example 1. Growth conditions included 42/25/600 10 Sccm (standard cubic centimeters per second) CH4/Ar/H2 at 330 x 1〇2 Pa and substrate temperature 880 ° C, adding 24 ppm N2. The substrate was removed and the resulting CVD layer was polished to 1.04 carats of rectangular cut CVD gemstones. , rated by the Diamond Grading Expert as having a special dark orange brown with a quality rating of SI1. 15 Gems at 1600 ° C 'at about 6.5 X 1 〇 9 Pa (65 kPa) The stone was annealed under steady pressure for 4 hours. After the annealing treatment, the gemstone was again rated by the same diamond grading expert, and it was judged that the diamond had a very strong brown peach color and had a quality grade of SI1. Example 8 20 has a very dark brown thickness The L3 mm CVD layer was grown on a {100} ΗΡΗΤ synthetic substrate in a manner similar to that described in Statement W 37 1355371. Growth conditions included 30/25/300 sccm (standard cubic centimeters per second) CH4/Ar/H2 at 330 X 1〇2 Pa and a substrate temperature of 780 °C with the addition of 46 ppm 15N2. The nitrogen isotopes used are 15N, and due to this quality effect, 15N may have an absorption line associated with nitrogen-containing defects that are normally used for the translocation of the value. The substrate was taken out, and a polishing sheet for an annealing test was produced from the CVD layer. The processing conditions are listed below. Slice Temperature (°C) Time Pressure Final Color 1 1800 4 hours 6·5 X 109 Pa Green 2 1700 4 hours 6_5 X 109 Pa Orange 3 1500 4 hours Atmospheric Orange Brown 4 1400 4 hours Atmospheric Brown 5 1200 4 hours Atmospheric Brown

After all the annealed sections, the sections annealed at atmospheric pressure (under argon) at 1200 ° C, 140 〇t, and 1500 °C showed an increase in the transmission of the visible light region by 10' corresponding to an increase in brightness. The absorption spectrum of the sample shows multiple lines, and the detailed list is as follows. The first table (strong, medium, weak, and very weak) has an approximate concept for the relative size of each feature in the spectrum. When not stated, it indicates that the relevant features are not observed. In the second table, "Yes" indicates that the relevant features are observed. From this table, it can be seen that the diamond grown and annealed by the method of the present invention exhibits an absorption line which is not seen in the CVD diamond grown by the fifteenth. A variety of absorbent lines have not appeared in diamonds previously made in any other manner, and such absorbent lines are clearly the unique absorption lines of the diamonds produced by the method of the present invention. The most notable examples are marked with an asterisk in the table. Many of these lines also appear in the light. 38 1355371 Wavelength (nano) If grown 1200 ° C 1400. . 1500 °C 1700 °C 1800 °C 270 nm band strong and strong 365 nm band strong 503 weak and weak 510 nm band in the middle and middle 512 weak and weak 553 weak strong pole Weak 597 Medium and Very Weak 624 Middle 637 Weak Weak Medium Weak Medium Weak 667* Very Weak Medium Weak Weak Weakness 684* Weak Weak Weakness Weakness 713 Very Weak Medium, Medium, Weak, 781* Medium, Medium, Weak, 851* Very Weak Weak medium strong and strong 1000 band strong strong and strong 1263* Middle middle 1281* Middle middle 1359 Strong strong weak 1556 Medium and medium weak °C 1500°C 1700. 1800°C 1332 Yes Yes Yes Yes Yes 1340* Yes Yes Yes 1344 Yes Yes Yes Yes Yes 1353 Yes Yes Yes Yes Yes 1362 Yes Yes Yes Yes 1371 Yes Yes Yes Yes Yes Yes 1374* 1378* Yes Yes 1384* Yes Yes 1396* Yes Yes 1405 Yes Yes 1453* Yes Yes 2695 Yes Yes Yes Yes Yes 2727 Yes Yes Yes Yes Yes 2807 Yes Yes Is it normal CH mode is yes or yes is 2949 Yes Yes Yes Yes 3031 Yes Yes Yes Yes 3054 Yes Yes Yes Yes 3107 Yes 3124 Yes Yes Yes 3310* Yes Yes 3323 Yes 4677* Yes Yes 1355771 [Simple description of the diagram] Figure 1 is annealed at 2400 ° C for 4 hours at a pressure of about 8.0 X 109 Pa (80 kbar), (a) before annealing and (b) after recording after annealing. 4 Aster ray-visible absorption spectrum. 40 1355371 Figure 2 is annealed at 1900 ° C for about 4 hours at a pressure of about 7.0 x 109 Pa (70 kbar), (a) before annealing and (b) after annealing The ultraviolet-visible absorption spectrum of the sample Ex-5 was recorded. Figure 3 was annealed at 1600 ° C for about 45 hours at a pressure of about 6.5 X 109 Pa (65 kbar), (a) before annealing and (b) The ultraviolet-visible absorption spectrum of the sample Ex-6 recorded after annealing. Figure 4 is annealed at 1600 ° C for 4 hours at a pressure of about 6.5 X 109 Pa (65 kbar), (a) before the annealing and (b) after annealing, the sample Ex-6 is UV-visible. The CIELAB a* value and the b* value derived from the absorption spectrum are plotted. 10 Figure 5 is annealed at 1600 ° C for 4 hours at a pressure of approximately 6.5 X 109 Pa (65 kbar), (a) before annealing and (b) after annealing an ex-violet of sample Ex-6 - A plot of CIELAB L* values and C* values derived from visible light absorption spectroscopy. [The main components of the diagram represent the symbol table] (none) 41

Claims (1)

1355371 PT.24 ffifr θ Z S92125957 Patent Application Patent Revision Amendment Revision Period: 100.8.24 U :... Patent Application Range: 1. A method for manufacturing single crystal CVD diamonds of the desired color, including the following Column step: providing a colored single crystal CVD diamond and heat treating the diamond at a temperature ranging from 1200 ° C to 2500 ° C at a steady pressure of the diamond or under an inert atmosphere or a stable atmosphere. 2. The method of claim 1, wherein the single crystal CVD diamond is in a layered form. 3. The method of claim 2, wherein the single crystal CVD diamond has a thickness greater than 1 mm. The method of claim 3, wherein the single crystal CVD diamond layer has a uniform crystal quality in its thickness. 5. The method of claim 2, wherein the single crystal CVD diamond is in the form of a small piece of the layer. 6. The method of claim 5, wherein the single crystal CVD diamond is a gemstone. 7. The method of claim 6, wherein the gemstone has three orthogonal dimensions, each dimension exceeding 1 mm. 8. The method of claim 1, wherein the single crystal CVD diamond has a nitrogen concentration of 0.05-50 ppm in a solid diamond. 20 9. The method of claim 8, wherein the lower limit of the range is 0.1 ppm 〇 10. The method of claim 8 wherein the lower limit of the range is 0.2 ppm ° 11. The method of the eighth item, wherein the lower limit of the range is 0.3 42 1355371 Patent Application No. 092125957, the scope of the patent application is amended, the revision period is: 100.8.24 ppm ° 12. The method of claim 8 wherein the range is The upper limit is 30 ppm 〇13. The method of claim 8 wherein the upper limit of the range is 20 5 ppm ° 14. The method of claim 8 wherein the upper limit of the range is 10 ppm 〇 15 20. The method of claim 1, wherein the CVD diamond is produced by a synthesis method using a gas phase, and the nitrogen concentration in the gas phase is in the range of 0.5 ppm to 500 ppm. 16. The method of claim 15, wherein the nitrogen concentration in the gas phase is in the range of from 1 ppm to 100 ppm. 17. The method of claim 15, wherein the nitrogen concentration in the gas phase is in the range of from 2 ppm to 30 ppm. 18. The method of claim 1, wherein the dominant color of the CVD diamond after heat treatment is not brown. 19. The method of claim 1, wherein the CVD diamond color is in the range of peach-green after heat treatment. 20. The method of claim 19, wherein the heat treated CVD diamond has a peach color. 21. The method of claim 19, wherein the CVD diamond color after the heat treatment is a premium peach color. 22. The method of claim 19, wherein the CVD diamond color after the heat treatment is green. 43 1355371 Patent Application No. 092125957, the scope of the patent application, the stipulation of the stipulation of the stipulation of the ninth aspect of the invention, in which the color of the CVD diamond after the heat treatment is a special green color. 24. The method of claim 1, wherein the CVD diamond is nearly colorless after heat treatment. 5. The method of claim 1, wherein the CVD diamond is colorless after heat treatment. 26. The method of claim 1, wherein the CVD diamond has a hue angle of less than 65 degrees after heat treatment. 27. The method of claim 1, wherein the CVD diamond has a hue angle of less than 60 degrees after heating 10 treatment. 28. The method of claim 1, wherein the CVD diamond has a hue angle of less than 55 degrees after heat treatment. 29. The method of claim 1, wherein the CVD diamond has a hue angle of less than 50 degrees after heat treatment. The method of claim 1, wherein after the heat treatment, the 1 mm thick parallel layer made of the diamond has a CIE Lab b* coordinate in the range of 0Sb*S8. 31. The method of claim 1, wherein after the heat treatment, the 1 mm thick parallel layer made of the diamond has a CIE Lab b* coordinate 20 in the range of 〇Sb*S4. 32. The method of claim 1, wherein after the heat treatment, the 1 mm thick parallel layer made of the diamond has a CIE Lab b* coordinate in the range of 04=^2. 33. The method of claim 1, wherein after the heat treatment, the patent application scope of the patent application No. 092125957 is amended by the patent: 100.8.24 The thickness of the diamond is 1 mm parallel layer It has the CIE Lab b* coordinate in the range of 〇Sb*Sl. 34. The method of claim 1, wherein after the heat treatment, the 1 mm thick parallel layer made of the diamond has a saturation (C*) of less than 10. 35. The method of claim 1, wherein the 1 mm thick parallel layer made of the diamond has a saturation (C*) of less than 5 after heat treatment. 36. The method of claim 1, wherein after the heat treatment, the 1 mm thick parallel layer made of the diamond has a saturation (C*) of less than 2. 37. The method of claim 1, wherein the heat treatment is carried out under conditions suitable to increase, modify, reduce or remove the absorption band or other component that contributes to color. 15 • 38. The method of claim 1, wherein the heat treatment is performed under conditions suitable to reduce the concentration of defects causing absorption in a broad spectrum of the spectrum. 39. The method of claim 1, wherein the single crystal CVD diamond has an absorption band taken at about 350 nm, and the heat treatment is carried out under conditions suitable to modify the absorption band in a manner that enhances the color of the diamond. The method of claim 1, wherein the single crystal CVD diamond has an absorption band taken at about 510 nm, and the heat treatment is carried out under conditions suitable to change the absorption band in a manner to enhance the color of the diamond. 41. The method of claim 39, wherein the change in the absorption band is a reduction or removal of the absorption band. </ RTI> </ RTI> </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; The red zone of visible light; and the heat treatment are carried out under conditions suitable for enhancing the color of the diamond to change the absorption band. 5 43. The method of claim 42, wherein the absorption band is altered to reduce or increase the strength of the absorption band. 44. The method of claim 1, wherein the heat treatment is carried out at a rock at a steady pressure of at least 1600 °C. 45. The method of claim 44, wherein the heat treatment is carried out at a temperature between at least 1600 and 1700 ° C under a steady pressure of 10 stone. 46. The method of claim 1, wherein the heat treatment is carried out at a temperature not exceeding 1900 ° C at a pressure in the graphite stabilizing zone under an inert atmosphere or a stable atmosphere. 47. The method of claim 1, wherein the heat treatment is carried out at a temperature of not more than 1800 ° C, at a pressure in the graphite stabilizing zone, under an inert atmosphere or a stable atmosphere. 48. The method of claim 1, wherein the heat treatment is carried out at a temperature not exceeding 1600 ° C at a pressure in the graphite stabilizing zone under an inert atmosphere or a stable atmosphere. The method of claim 46, wherein the heat treatment is carried out at a temperature not exceeding 1400 ° C at a pressure in the graphite stabilizing zone under an inert atmosphere or a stable atmosphere. 50. The method of claim 46, wherein the inert atmosphere is argon. 46 1355371 5 _· Patent Application No. 092125957 Patent Application Revision This revision period: 100.8.24 51. A single crystal diamond layer manufactured by the method of claim 1 for optical applications . 52. A single crystal diamond layer produced by the method of claim 1 of the patent application, for use as an electromagnetic transmission window. 53. A single crystal CVD diamond layer produced by the method of claim 1 having a color ranging from peach to green. 54. The single crystal CVD diamond layer of claim 53 wherein the color is a premium peach color. 55. A single crystal CVD diamond layer as claimed in claim 53 wherein the color 10 « i is extra green. 56. A single crystal CVD diamond layer as claimed in claim 53 having a thickness of at least 1 mm. 57. A single crystal CVD diamond layer as claimed in claim 53 which has a uniform crystal quality in its thickness. 15 • 58. — Small single crystal CVD diamond produced by a single crystal CVD diamond layer as in claim 53 of the scope of the patent application. 59. A small piece of single crystal CVD diamond according to claim 58 of the patent application, which has a shape of a stone. 60. The small single crystal CVD diamond of claim 59, which has three 20 orthogonal dimensions, each dimension exceeding 1 mm each. 47