Method of thermal treatment of single-crystal substrate znte and single-crystal substrate znte |
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IPC classes for russian patent Method of thermal treatment of single-crystal substrate znte and single-crystal substrate znte (RU 2411311):
 
 Method for manufacturing substrate for thick-film high-temperature superconductor circuit / 2262152
Proposed method used in manufacturing thick-film high-temperature superconductor circuit includes low-temperature firing of substrate followed by laser milling of grooves for paste and scanning with laser beam of area
 A method of manufacturing n - p transitions in single crystals of cdxhg1-xte / 2062527
The invention relates to the field of semiconductor technology and can be used in the manufacture of n p-transitions for the production of photodetectors (AF) infrared (IR) radiation
 Method of making silicon-on-insulator structures / 2382437
Invention relates to semiconductor engineering and can be used for making device structures. In the method of making silicon-on-insulator structures, an amorphous layer of SiO2 dielectric is formed on a Si substrate and impurities of reactive gases with low solubility in SiO2 are implanted in the layer, forming molecules which easily diffuse to the surface. The substrate is then annealed in an oxidative atmosphere. During annealing, complexes are formed from gas molecules of the implanted impurities and oxygen, where the said complexes interact with atoms on the SiO2 surface, with modification of the surface due to saturation of the broken bonds of atoms and formation of brand new bonds more than the initial number, which interact with OH complexes with hydrophilisation. In the silicon donor-substrate, a weakened zone is created through ion implantation, where the said zone separates the silicon layer transferred to the substrate. The donor-substrate and the substrate undergo cleaning and hydrophilisation. Further, the substrate and the donor-substrate are joined in pairs. Joining and simultaneous layering are carried out on the weakened zone to form a cut off surface layer of silicon on the substrate.
Method of preparing semiconductor structure / 2378740
Invention can be used in production of semiconductor devices. In the method of preparing a semiconductor structure on a silicon wafer an n+ type layer is formed on which an epitaxial n type layer is grown. Further, in the n+ layer, a double layer porous structure with different density is created, the upper layer having pore size from 2 to 8 nm and the lower layer having pore size two orders larger, through successive variation of current density from 30 mA/cm2 to 45 mA/cm2 with subsequent application of a three-stage oxidation mode: at temperature 300-400°C for one hour in dry oxygen; at temperature 800-900°C for two hours in dry oxygen; at temperature 1000-1100°C for one hour in wet oxygen.
 Method for manufacturing of silicon-on-insulator structure / 2368034
Invention is related to semiconductor technology and may be used to manufacture device structures. In method for production of silicon-on-insulator structure, insulating layer is generated on substrate surface, and ions of weakly soluble and easily segregating admixture of reactive gases are implanted in it. Conditions of implantation provide for concentration of introduced admixture, which exceeds solubility limit and which, in process of annealing, results in generation of endotaxial layer of dielectric, but insufficient for ion synthesis of precipitates. In donor substrate ion implantation is used to create weakened zone, which extracts layer transferred to insulating layer of substrate. Then chemical treatment of substrate and donor substrate is carried out, and they are connected by insulating layer and layer transferred to substrate, intertwined and stratified in weakened zone with generation of cut-off surface layer on substrate. Further high-temperature treatment is used to segregate implanted admixture to its border of interface with cut-off surface layer, and intermediate insulating layer is grown on specified border.
Pre-epitaxial process of polished silicon carbide substrates / 2345443
Invention refers to semiconductor engineering. Pre-epitaxial process of polished silicon carbide substrates involves consistent procedures as follows: monocrystal calibration, primary flat sawing, monocrystal slicing, wafer grinding, edge cutting, wafer polishing, chemical and hydromechanical washing of wafer surfaces, centrifuge drying and vacuum packing. Centrifuge drying or unpacking is followed with free wafer annealing in vacuum furnace at temperature 800-1200°C that precedes epitaxy.
Method of semiconductor instrument manufacturing with low flaw density / 2330349
Before silicon film epitaxial growth stage a sapphire substrate is processed with oxygen ions in amount of 5·1012-1·1013 cm-2 with energy 15-30 keV, and further is annealed at the temperature of 300°C for 35 seconds.
 Method for heterostructure manufacture / 2301476
Proposed method for heterostructure manufacture includes implantation of ions on surface whereon amorphous layer is formed in advance, implantation of slightly soluble ions and easily segregating admixtures or slightly soluble and easily segregating admixtures in substrate amorphous layer under implantation conditions affording implanted admixture concentration exceeding theoretically possible solubility limit and leading to formation of semiconductor epitaxial layer of at least one single layer thickness, as well as implantation of hydrogen into semiconductor wafer to form intercepted semiconductor layer; then intercepted semiconductor layer is formed on substrate incorporating amorphous layer on its working surface under conditions ensuring its hydrogen-induced transfer from semiconductor wafer, this being followed by baking under conditions affording segregation of admixture implanted in substrate amorphous layer to intercepted semiconductor layer-amorphous layer interface and epitaxial growth of single-crystalline semiconductor layer of implanted admixture or compounds of implanted admixtures on mentioned interface.
 Method for producing silicon-on-insulator structure / 2265255
Proposed method for producing silicon-on-insulator structure involves hydrogen implantation in silicon wafer followed by chemical treatment of the latter and substrate, jointing of silicon wafer with substrate, jointing and separation along implanted layer of wafer with cut-off silicon layer being transferred to substrate; upon separation along implanted layer wafer is annealed to remove radiation defects and additionally annealed to provide for dissolution of oxygen precipitates introduced in material during thermal pretreatment processes. Annealing intended to remove radiation defects is conducted at 1100 °C for 0.5 - 1 h. Hydrogen is implanted in silicon wafer through pre-grown thin silicon oxide layer of 20 - 50 nm which is then removed. Proposed method uses for implantation hydrogen ions H+ 2 at dose rate of (2.5 - 5) x 1016 cm2. Silicon wafer is joined to and separated from silicon wafer along its implanted layer at temperature ranging between 300 and 600 °C for 0.5 - 2 h. Silicon wafer is joined to and separated from substrate in vacuum of 10 - 105 Pa and further jointing and separation along implanted layer of silicon wafer is conducted at temperature ranging between 300 and 600 °C for 0.6 - 2 h. Additional annealing resulting in dissolution of oxygen precipitates introduced in material during its pretreatment processes is conducted in wet oxygen atmosphere at temperature of 1200 °C for 0.5 - 2 h. Additional annealing resulting in dissolution of oxygen precipitates introduced in material during thermal pretreatment is conducted in nitrogen atmosphere at temperature of 1200°C for 0.5 - 2 h.
 Method of forming of polycrystalline silicon layers / 2261937
The offered invention is pertaining to the field of microelectronics, in particular, to the methods of manufacture of microcircuit chips. The offered method includes a loading of semiconductor slices in a reactor having hot walls perpendicularly to a gas stream, pumping-out of the reactor air up to the ultimate vacuum, introduction of monosilane for deposition of layers of polycrystalline silicon, silane supply cutoff, pumping-out of the reactor air up to the ultimate vacuum, delivery of a noble gas into the reactor up to atmospheric air pressure, unloading of the semiconductor slices from the reactor. After introduction of the noble gas into the reactor conduct an additional thermal annealing of layers of polycrystalline silicon at the temperature of no less than 1323K, then keep the slices at this temperature during 40-60 minutes in a stream of noble gas and reduce the temperature down to the temperature of the polycrystalline silicon layers growth. The technical result of the invention is a decrease of heterogeneity of resistance of the polycrystalline silicon layers.
 Heterostructure manufacturing process / 2244984
Proposed heterostructure manufacturing process that provides for manufacturing crystal films of homogeneous thickness, 10 to 300 nm thick, on amorphous insulator, semiconductor material, and other substrates, including flexible ones, at surface roughness of film about 0.2 - 0.5 nm involves introduction of hydrogen in working wafer, chemical treatment of the latter, joining of working wafer and substrate, splicing and exfoliation of working wafer including transfer of film to heterostructure. Formed in working wafer prior to hydrogen introduction is buried interface to display layer in wafer transferred as film to heterostructure or buried interface with delta-doped layer of impurity or thin layer in the form of impurity compounds also displaying layer in working wafer is formed and transferred as film to heterostructure; upon chemical treatment working wafer and substrate are dried out, then adsorbed substances are removed from and adhesive layer applied to them, working wafer and substrate are spliced and exfoliated with film transferred to heterostructure at temperature keeping hydrogen introduced in working wafer inside its space and affording hydrogen accumulation on buried interface or on delta-doped buried interface, or in the form of impurity compounds, hydrogen being introduced in working wafer through depth greater than or of same order of magnitude as burial depth of buried interface or delta-doped buried interface, or in the form of thin layer of dope compounds.
 Method of growing heat resistant monocrystals / 2404298
Crystals are grown using the Kyropoulos method with an optimum annealing mode, carried out while lowering temperature of the grown monocrystal to 1200°C at a rate of 10-15°C/hour and then cooling to room temperature at a rate of 60°C/hour.
Method of producing monocrystals of calcium and barium flourides / 2400573
Method involves crystallisation from molten mass through Stockbarger method and subsequently annealing the crystals through continuous movement of the crucible with molten mass from the upper crystallisation zone to the lower annealing zone while independently controlling temperature of both zones which are separated by a diaphragm. The crucible containing molten mass moves from the crystallisation zone to the annealing zone at 0.5-5 mm/h. Temperature difference between the zones is increased by changing temperature in the annealing zone proportional to the time in which the crucible moves from the beginning of crystallisation to its end, for which, while maintaining temperature in the upper crystallisation zone preferably at 1450-1550°C, in the lower annealing zone at the beginning of the crystallisation process temperature is kept at 1100-1300°C for 30-70 hours, thereby ensuring temperature difference of 450°C between the zones at the beginning. Temperature of the annealing zone is then lowered to 500-600°C in proportion to the speed of the crucible with the growing crystal. Temperature of the annealing zone is then raised again to 1100-1300°C at a rate of 20-50°C/h, kept for 18-30 hours after which the zone is cooled to 950-900°C at a rate of 2-4°C/h, and then at a rate of 5-8°C/h to 300°C. Cooling to room temperature is done inertially. Output of suitable monocrystals of calcium and barium fluorides with orientation on axes <111> and <001>, having high quality of transparency, uniformity, refraction index and double refraction is not less than 50%.
 Superstrong single crystals of cvd-diamond and their three-dimensional growth / 2389833
Method includes placement of crystalline diamond nucleus in heat-absorbing holder made of substance having high melt temperature and high heat conductivity, in order to minimise temperature gradients in direction from edge to edge of diamond growth surface, control of diamond growth surface temperature so that temperature of growing diamond crystals is in the range of approximately 1050-1200°C, growing of diamond single crystal with the help of chemical deposition induced by microwave plasma from gas phase onto surface of diamond growth in deposition chamber, in which atmosphere is characterised by ratio of nitrogen to methane of approximately 4% N2/CH4 and annealing of diamond single crystal so that annealed single crystal of diamond has strength of at least 30 MPa m1/2.
 Ceramic laser microstructured material with twinned nanostructure and method of making it / 2358045
Proposed laser material is a ceramic polycrystalline microstructure substance with particle size of 3-100 mcm, containing a twinned nanostructure inside the particles with size of 50-300 nm, made from halides of alkali, alkali-earth and rare-earth metals or their solid solutions, with vacancy or impurity laser-active centres with concentration of 1015-1021 cm-3. The method involves thermomechanical processing a monocrystal, made from halides of metals, and cooling. Thermomechanical processing is done until attaining 55-90% degree of deformation of the monocrystal at flow temperature of the chosen monocrystal, obtaining a ceramic polycrystalline microstructure substance, characterised by particle size of 3-100 mcm and containing a twinned nanostructure inside the particles with size of 50-300 nm.
Method for thermal processing of semi-finished abrasive tools on organic thermosetting binding agents / 2351696
Invention is related to the field of abrasive processing and may be used in production of abrasive tools for polishing of blanks from different metals and alloys. Full cycle of thermal processing of semi-finished abrasive tools on organic thermosetting binding agents includes stages of preliminary heating and hardening in microwave field of SHF- chamber with frequency of 2450 MHz for abrasive tool with thickness of up to 100 mm and with frequency of 890 - 915 MHz for abrasive tool with thickness of more than 100 mm. Prior to SHF-thermal processing semi-finished abrasive tools are placed into radio transparent steam-and-gas permeable container-thermostat. After temperature of thermosetting binding agent complete polymerization has been achieved, and after pause at this temperature, thermostat is withdrawn from SHF-chamber, and semi-finished abrasive tools are kept in thermostat until their temperature drops at least by 80°C. After that thermostat is opened, semi-finished products are cooled in open air and then withdrawn from thermostat.
Method for thermal treatment of half-finished abrasive tools on organic thermosetting binders / 2349688
Group of half-finished abrasive tools prior to thermal treatment is placed into thermally insulated steam and gas permeable radiolucent thermostat. Full cycle of mentioned half-finished articles thermal treatment is carried out. Cycle includes stages of preliminary heating and hardening of half-finished items group in microwave field of SHF-chamber with frequency of 2,450 MHz for abrasive tools with thickness of up to 100 mm and frequency of 890...915 MHz for abrasive tools with thickness of more than 100 mm to achieve temperature of organic thermosetting binder complete polymerisation with further maintenance at this temperature. In process of SHF thermal treatment volatile substances are forcedly and uniformly removed from free volume of thermostat through slots arranged in front and back walls of thermostat. Possibility for vapours of volatile substances to be saturated is eliminated with preservation of maximum possible effect of thermostat working area thermal insulation effect and provision of half-finished items temperature difference that does not exceed ±10% of its average level inside thermostat.
 Method of obtaining synthetic minerals / 2346887
Invention concerns obtaining synthetic minerals and can be applied in technics and jewellery. Method of artificial mineral synthesis is implemented by crucible method involving blend processing in plasma torch of plasmotron to obtain melt, melt drop feeding into crucible by plasma-forming gas flow with further crystallisation. Seeding agent is placed at crucible bottom in advance, and synthesis is performed at plasmotron output of 12 kW and blend feed rate of 2-3 g/min with simultaneous annealing of the melt crystallised on seeding agent in annular furnace for 2-3 hours at 1000°C. Preliminary placement of seeding agent to crucible bottom ensures accelerated crystal growth and higher process performance. Simultaneous annealing of artificial minerals reduces tension in end product significantly.
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FIELD: electricity. SUBSTANCE: method includes the first stage of increasing temperature of single-crystal substrate ZnTe up to the first temperature of thermal treatment T1 and maintenance of substrate temperature within specified time; and the second stage of gradual reduction of substrate temperature from the first temperature of thermal treatment T1 down to the second temperature of thermal treatment T2, lower than T1 with specified speed, in which T1 is established in the range of 700°C≤T1≤1250°C, T2 - in the range of T2≤T1-50, and the first and second stages are carried out in atmosphere of Zn, at the pressure of at least 1 kPa or more, at least 20 cycles or at least 108 hours. EFFECT: invention makes it possible efficiently to eliminate part of Te deposits without considerable deterioration of efficiency and improvement of light transmission of single-crystal substrate ZnTe. 5 cl, 3 dwg
The technical field to which the invention relates. The present invention relates to a method of improving the crystallinity of the single crystal semiconductor compounds II-VI groups, suitable as a substrate for light modulation element. In particular, the present invention relates to a heat treatment to eliminate the deposits that are included in the ZnTe crystal, to improve light transmission. Prior art Because the crystal of a semiconductor compound includes item 12 (2B) group and item 16 (6B) group of the Periodic table (hereinafter referred to as semiconductor compound II-VI group) has a different width of the forbidden zone, the crystal has different optical characteristics. In addition, the semiconductor compound II-VI group, as expected, could be applied, for example, as a material of the light modulation element. However, in the case of semiconductor compounds II-VI group, since it is difficult to control the stoichiometric composition (stoichiometry), it is difficult to grow a good solid crystal usual methods of manufacture. For example, ZnTe composition at the melting point is shifted to Those from the stoichiometric composition. Thus, in growing crystals there is some possibility that will remain fat, which is probably caused by an excess of Those. Because Those deposits have sizes of several μm with a specific gravity of about 105cm-3, Those deposits cause a noticeable decrease in performance in a single-crystalline ZnTe substrate. Such monocrystalline substrate ZnTe with such low light output is not suitable for light modulation element or the like when using electro-optic effect, in which the laser light passes through the crystal with a thickness of about 10 mm In reception quality, reduce sediment in the ZnTe single crystal, there is a method of epitaxial growth of single crystals of ZnTe. In accordance with the specified method can be used to produce single crystals of ZnTe with excellent crystallinity. The authors of the present invention proposed a method of producing single crystal semiconductor compounds II-VI group, which includes at least: the first stage of increasing the temperature of the single crystal semiconductor compounds II-VI group to the first temperature heat treatment (T1) and the temperature of the crystal within a predetermined time and the second stage of gradual reduction of the crystal temperature from the first temperature heat treatment T1 to the second temperature thermal treatment T2 that is lower than the temperature of the heat treatment T1 with a predetermined speed (Tiled application P 2004-158731). In accordance with the disclosure of the invention in tiled application JP 2004-158731 at the first stage it is possible to remove deposits composed of an element of group 16 (e.g., Te) and in the second stage it is possible to remove deposits, consisting of polycrystals, etc. Disclosure of inventions However, although the above method of epitaxial growing effective for growing single crystals of ZnTe with a relatively small thickness (for example, about several μm), requires excessive time and costs for growing single crystals of ZnTe with a thickness of 1 mm or more. This method is not a real choice. In addition, although the above-mentioned thermal treatment method, disclosed in application laid JP 2004-158731, effective and can eliminate Those deposits in a single-crystalline ZnTe substrate with a thickness of 1 mm, it was found that this method is not always effective for substrates with a thickness of 1 mm or more, used for light modulation element or the like, since in some cases not achieved a sufficient effect of thermal processing. More precisely, if the thickness of the single crystal ZnTe substrate is 1 mm or more when the heat treatment (the first stage + second stage) for about 100 hours with regard to performance in the above method, heat treatment, quenching the TCI tiled application JP 2004-158731, the transmittance of single-crystal of ZnTe substrate obtained after the heat treatment (at a wavelength of 1000 nm is 50% or less and is not suitable for use for light modulation element or the like. It was also investigated cross-section of the polycrystalline ZnTe substrate an optical microscope. In the cross section of the deposits were not observed in the field with a depth of about 0.20 mm from the surface. However, in more intimate areas remain fat The size of 3-10 μm and with the same proportion that the crystal before heat treatment. For single-crystalline ZnTe substrate with a thickness of 1 mm or more had a transmittance (wavelength 1000 nm) 50% or more, with the method of heat treatment as disclosed in laid application JP 2004-158731 requires heat treatment for 200 hours or more depending on the temperature of heat treatment. It is obvious that the performance is significantly degraded. Thus, the authors of the present invention believe that the method of heat treatment in accordance with the above-mentioned earlier application is effective for removing Those deposits, but can be further improved. Thus, the authors of the present invention intensively studied a method of heat treatment of single crystal unnatural semiconductors the new connection ZnTe. The aim of the present invention is to provide a method of heat treatment to effectively address Those deposits in a single-crystalline ZnTe substrate and a single crystal ZnTe substrate with a thickness of 1 mm or more optical characteristics, suitable for light modulation element or the like. The present invention is a method of heat treatment of single crystal ZnTe substrate, comprising: a first stage of raising temperature single crystal ZnTe substrate to the first temperature heat treatment T1 and maintaining the substrate temperature within a predetermined time; and a second stage of gradual reduction of the substrate temperature from the first temperature heat treatment T1 to the second temperature thermal treatment T2, which is lower than the temperature of the heat treatment T1 with a predetermined speed at which the first temperature heat treatment T1 set in the range 700°C≤T1≤1250°C, and the second temperature of the heat treatment T2 set in the range T2≤T1-50. The first and the second stage is performed in the atmosphere of Zn, at least at 1 kPa or more. In particular, this method is effective for single-crystalline ZnTe substrate with a thickness of 1 mm or more, which is used for light modulation element or the like. When the first and second studieperiode as a cycle, the first and second stages may cyclically repeated a predetermined number of times. In a single-crystalline ZnTe substrate for light modulation element in accordance with the present invention, when the thickness of the substrate is 1 mm or more, deposits, included in the crystal, have dimensions of 2 μm or less and a density below 200 cm-3. The above-mentioned single crystal ZnTe substrate has a transmittance of 50% or more for light beam with a wavelength of 700-1500 nm. In particular, single crystal ZnTe substrate has a transmittance of 60% or more for light beam with a wavelength of from 900 to 1,500 nm. The above method of thermal processing in accordance with the present invention it is possible to obtain single-crystalline ZnTe substrate, as described above. The invention is as follows. First, when the authors of the present invention have applied the single-crystalline ZnTe substrate with a thickness of 2 mm or more is used as the light modulation element or the like, in the way of heat treatment described in tiled application JP 2004-158731 appeared the above-mentioned problem. To solve the above problems, the authors of the present invention investigated the conditions of heat treatment of the above method of thermal processing. The temperature of the monocrystalline substrate ZnTe increase to invoicemaster heat treatment T1 with a predetermined speed (for example, 15°C/min) and keep the temperature of the substrate within a predetermined time (for example, 2 hours) (first stage). Then the temperature of the substrate is gradually reduced to a predetermined speed (for example, 0.3°C/min) until the second temperature thermal treatment T2 lower than the first temperature heat treatment T1, 60°C. (second stage). Then, when the first and second stages of taking cyclical (approximately 5.4 hours), the first and second stages are performed with the single-crystal ZnTe substrate a predetermined number of cycles. In the case of the method of heat treatment in which heat treatment is performed with the single-crystal ZnTe substrate in the atmosphere of Zn to reduce deposits in accordance with the above-mentioned earlier application is believed that the heat treatment time depends on the speed of diffusion of Zn. Therefore, the deposits of Those remaining in the single crystal ZnTe substrate after the heat treatment, are investigated using time heat treatment (number of cycles) and temperature parameters. To confirm the effect of Zn diffusion due to the heat treatment applied relatively thick single-crystalline ZnTe substrate with a thickness of about 4 mm In particular, heat treatment is performed with the single-crystal ZnTe substrate at the first temperature termicheskaya T1 650°C, 750°C and 850°C and during the time of heat treatment (number of cycles) 54 hours (10 cycles), 108 hours (20 cycles) and 216 hours (40 cycles). In the above-mentioned earlier application, the first temperature heat treatment T1 is in the range of 0,5M≤T1≤0,65M (M is the melting point). That is, since the melting point of ZnTe equal 1239°C., the first temperature heat treatment T1 is in the range 619,5≤T1≤805,35. Table 1 represents the area in which sediments in the monocrystalline substrate ZnTe disappear after the above heat treatment, indicating the depth from the surface. As indicated in table 1, if the first temperature heat treatment T1 is equal to 650°C, the area no scale is 0.5 mm from the surface, even when the heat treatment time is 216 hours (40 cycles). On the other hand, if the first temperature heat treatment T1 is equal to 750°C, the area without deposits is 0.9 mm from the surface, when the heat treatment time is 108 hours (20 cycles). If the first temperature heat treatment T1 is equal to 850°C, the deposition disappears completely at the time of heat treatment, equal to 108 hours (20 cycles). Since Zn diffuses from two sides of the substrate, it was found that the area which had disappeared deposits, is 2.0 mm or more, where the area defined is eleesa depth from the surface.
Then in a single-crystalline ZnTe substrate, which carried out the specified heat treatment, determine the transmittance when the passage of a beam of light with a wavelength of 700-1500 nm in a single-crystalline ZnTe substrate. In the single-crystalline ZnTe substrate, in which the fat has essentially disappeared when the first temperature heat treatment T1 is equal to 850°C. and the heat treatment time is equal to 108 hours (20 cycles)had a transmittance of 50% or more (at a wavelength of 700-1500 nm). Up Ter the systematic processing of the light transmission substrate was 50% or less (at a wavelength of 700-1500 nm). In addition, as a result of implementation of the experiments, performing heat treatment at the first temperature heat treatment of 700°C-1250°C at 20 cycles (108 hours) or more, it was found that single-crystalline ZnTe substrate has a transmittance of 50% or more (at a wavelength of 700-1500 nm). In particular, when the first temperature heat treatment of 850°C or more, deposits Those completely disappear by heat treatment of 20 cycles. It is established that the substrate is suitable for light modulation element. On the other hand, even when the first temperature heat treatment below 700°C, the implementation of heat treatment for 216 hours (40 cycles) substrate with a thickness of about 2 mm had a transmittance of 50% or more (at a wavelength of 700-1500 nm). However, conditions are not suitable as heat-treated conditions from the point of view of performance. Based on the above experimental result, the present invention is created on the basis of the fact that carrying out heat treatment of single crystal ZnTe substrate at the first temperature heat treatment T1 700-1250°C. and the second temperature thermal treatment (T1-50) or less effectively eliminates the part of Those deposits without any noticeable performance degradation and improve setprop the Scania monocrystalline substrate ZnTe. In accordance with the present invention is a method of thermal processing of single-crystalline ZnTe substrate includes: a first stage of increasing the temperature of the single crystal ZnTe substrate to the first temperature heat treatment T1 and maintaining the substrate temperature within a predetermined time and the second stage of gradual reduction of the substrate temperature from the first temperature heat treatment T1 to the second temperature thermal treatment T2 lower than the temperature of the heat treatment T1 with a predetermined speed at which the first temperature heat treatment T1 is in the range of 700°C≤T1≤1250°C. and the second temperature of the heat treatment T2 is in the range T2≤T1-50. It is therefore possible that the sediments in the monocrystalline substrate ZnTe effectively disappeared and it turns out that single-crystalline ZnTe substrate with high transmittance. Respectively can be achieved excellent characteristics of the light modulation element using a single crystal of ZnTe substrate, which is obtained by the above method of heat treatment, where the thickness of the substrate is 1 mm or more, deposits, included in the crystal, have dimensions of 2 μm or less and the proportion below 200 cm-3and in which the single-crystal substrate ZnTe has sweepr is the blowing up of 50% or more for light beam with a wavelength of 700-1500 nm. Brief description of drawings Figure 1 is a diagram representing the temperature profile of the heat treatment performed for a single crystal of ZnTe substrate. Figure 2 is a diagram representing the transmission single-crystalline ZnTe substrate before and after thermal processing. Figure 3 is a diagram representing the state of the surface (The deposition) single crystal ZnTe substrate before and after thermal processing. The best option of carrying out the invention Next is disclosed a preferred implementation of the present invention. This implementation uses the sample obtained in the following way (the substrate). Single-crystalline ZnTe substrate with a diameter of 2-3 inches and orientation of planes (100) or (110) are grown from the melt of gallium (Ga) as dopant. The resulting substrate is cut so as to obtain a thickness of 0.7 to 4.0 mm are used For the abrasive grains No. 1200 and perform etching the surface of Br23% Meon cut substrate for use as a sample (substrate). Before heat treatment on the single crystal substrate ZnTe single crystal substrate ZnTe and Zn is placed in a predetermined position in a quartz ampoule and the ampoule is sealed under vacuum of 1.0 PA or less. Then the quartz ampoule is placed in a diff is precise oven to perform the following thermal processing. Heat treatment in accordance with the specified implementation is performed in accordance with the temperature profile of figure 1. In particular, the part where you have placed the single crystal ZnTe substrate, is heated to the first temperature heat treatment T1=850°C at 15°C/min, for example, and the temperature of 850°C is maintained for 2 hours (first stage). The part where you have placed Zn, is heated so that the pressure of Zn P was 1.0 kPa or more. Then the temperature of the substrate is gradually reduced with a speed of 0.3°C/min to a second temperature thermal treatment T2 790°C (T2≤T1-50) (second stage). In particular, the heat treatment in the second stage is 60/0,3=200 minutes. Then, when the heat treatment, comprising the above-described first and second stage, i.e. the way in which the temperature of the single crystal ZnTe substrate is increased to the first temperature heat treatment T1, the temperature of the substrate is maintained for 2 hours and then the temperature of the substrate is reduced to a second temperature thermal treatment T2 is taken for one cycle (about 5.4 hours), the process is repeated 20 cycles (about 108 hours). After that, the temperature of the part in which you have placed monocrystalline substrate ZnTe, reduce to room temperature with a speed of, for example, 15°C/min and complete heat treatment. T is mperature part, encased Zn, similarly reduced to room temperature. Then spend processing and etching of single-crystalline ZnTe substrate, which is obtained after the heat treatment, under conditions similar to those in the previous processing. Then measure the transmittance and determine the state of the surface. Figure 2 is a diagram representing the transmission single-crystalline ZnTe substrate before and after heat treatment. As shown in figure 2, the single crystal ZnTe substrate obtained after the heat treatment, has a transmittance of 50% or more for light beam with a wavelength of 700 nm or more. On the other hand, single-crystalline ZnTe substrate, obtained before the heat treatment, has a transmittance of about 30% for a beam of light with a wavelength of 700 nm or more. Thus, it was confirmed that the transmittance is improved by performing heat treatment in accordance with the specified implementation. If any of the ZnTe single-crystal substrates with a thickness of 0.7 to 4.0 mm, the transmittance is equal to the above, is obtained regardless of the thickness. Because I believe that the decrease in light transmission is mainly caused by the reflection from the surface and light is poorly absorbed by the single crystal ZnTe, it is easy to assume that such a transmittance t is the train can be obtained for a single crystal of ZnTe substrate with a thickness of 4.0 mm or more. Figure 3 is a diagram showing the result of observation of the monocrystalline substrate ZnTe before and after the heat treatment specified implementation using optical microscope of transmission type. Figure 3(a) represents the result of the observation of single-crystalline ZnTe substrate to heat treatment. Figure 3(b) represents the result of the observation of single-crystalline ZnTe substrate after the heat treatment. As shown in figure 3(a), Those deposits are distributed in the substrate prior to thermal processing. It was confirmed by observation of the cross section of the substrate that deposits are Those with dimensions of 2 μm or more and a density of 105cm-3or more remain in the substrate. On the other hand, as shown in figure 3(b), confirmed that the deposits are Those with a size of 2 μm or more remaining in the substrate obtained after the heat treatment are not available. As described above, in accordance with the method of heat treatment in accordance with the implementation of Those deposits in a single-crystalline ZnTe substrate can be effectively eliminated, and the transmittance can be 50% or more for light beam with a wavelength of 700 nm or more. Thus, the use of single-crystalline ZnTe substrate, as described above, you can create a light modulation element with excellent characteristics. As described above, the image is eenie, created by the authors, is described in detail on the basis of option exercise. However, the present invention is not limited to the above implementation. For example, although the first temperature heat treatment T1 is 850°C in the above implementation, a single crystal ZnTe substrate with similar transmittance can be obtained by setting the first temperature heat treatment T1 in the range of 700-1250°C. In addition, the heat treatment time (exposure time) of the first stage and time of heat treatment (temperature reduction rate of the second stage is not particularly limited and can be appropriately changed. Although the second temperature thermal treatment T2 set lower than the first temperature heat treatment T1, at 60°C in the above implementation, the second temperature thermal treatment T2 may be set lower than the first temperature heat treatment T1, 50°C or more. Although the second temperature thermal treatment T2 may be room temperature, the second temperature thermal treatment T2 is preferably (T1-200)°C. or more preferably (T1-100)°C. or more from the industrial point of view. The present invention is a method of heat treatment of single crystal ZnTe substrate. However, predstavljaet is, that the present invention is effective in reducing deposits in the crystals of semiconductor compounds other main groups II-VI, non-ZnTe. 1. The method of thermal processing monocrystalline substrate ZnTe, including 2. The method of heat treatment of single crystal ZnTe substrate according to claim 1, in which the single crystal ZnTe substrate has a thickness of 1 mm or more. 3. The method of heat treatment of single crystal ZnTe substrate according to claims 1 and 2, in which Monocristalline the ZnTe substrate for light modulation element, processed according to any one of claims 1 to 3, which has a thickness of 1 mm or more, and deposits included in the crystal, have dimensions of 2 μm or less and the proportion below 200 cm-3and single-crystalline ZnTe substrate has a transmittance of 50% or more for light beam with a wavelength of 700-1500 nm. 5. Single-crystalline ZnTe substrate for light modulation element, processed according to any one of claims 1 to 3, which has a thickness of 1 mm or more, and deposits included in the crystal, have dimensions of 2 μm or less and the proportion below 200 cm-3and single-crystalline ZnTe substrate has a transmittance of 60% or more for light beam with a wavelength of from 900 to 1,500 nm.
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