Hard diamonds and method of its preparation

FIELD: chemistry.

SUBSTANCE: process of hard monocrystalline diamond preparation compises fixing of inoculating diamond in the holder and its growing by the way of chemical deposition from gaseous phase induced by microwave plasma. The process is implemented at temperature ca 1000°C - 1100°C in medium N2/CH4=0.2-5.0 and CH4/H2=12-20% at total pressure 120-220 torr. Derived monocrystalline diamond has the hardness in the range 50-90GPa and fracture strength 11-20MPa m1/2.

EFFECT: increasing of diamond hardness.

7 cl, 4 dwg

 

The present invention claims priority of the provisional application No. 60/486435, filed July 14, 2003, which is incorporated in this description by reference.

Confirmation of state law

The present invention is carried out with U.S. government support under grant number EAR-0135626 provided by the National Science Foundation. The U.S. government has certain rights to this invention.

Background of the invention

The technical field to which the invention relates.

The present invention relates to diamond and more specifically to a solid diamond produced using chemical vapor deposition, microwave induced plasma (MPCVD) in the deposition chamber.

Description of the prior art,

Large-scale production of synthetic diamond has long been the aim of both scientific research and industrial production. Diamond, in addition to its properties of a gemstone, is the hardest known substance, has the highest known thermal conductivity and is transparent in a wide spectrum of electromagnetic radiation. Therefore, diamond is highly valued because of the wide range of applications in several industries, along with its value as a gemstone. For at least the last twenty years has been dost the pen is a method of obtaining small amounts of diamond by chemical deposition from the gas phase (CVD). As reported B.V.Spitsyn in "Vapor Growth of Diamond on Diamond and Other Surfaces", Journal of Crystal Growth, vol.52, pp.219-226, the method is CVD diamond on a substrate using a combination of methane or other simple hydrocarbon gas and hydrogen gas at low pressures and temperatures of 800-1200°C. including hydrogen gas prevents the formation of graphite, while the formation of centers of crystallization and growth of diamond. In the case of use of this method have been reported growth rates of up to 1 μm/hour.

In subsequent work, for example work Kamo et al., reported in "Diamond Synthesis from Gas Phase in Microwave Plasma", Journal of Crystal Growth, vol.62, pp.642-644, shows the use of chemical vapor deposition, microwave induced plasma (MPCVD), to obtain a diamond at pressures 1-8 kPa within temperatures of 800-1000°C with a microwave power of 300 to 700 watts at a frequency of 2.45 GHz. In the specified way Kamo et al. used the concentration of methane gas 1-3%. In the case of using MPCVD method reported maximum growth rates of 3 μm/hour.

In the above methods and a number of recently developed methods to crack diamonds in some cases, better than natural diamonds. In particular, in the way that is faster growth, in which only get or grow a polycrystalline form of the diamond world is but getting diamond having crack resistance, better than natural diamonds. With the exception of some synthetic diamonds obtained under conditions of high temperature and high pressure (HPHT), which was subjected to annealing, most diamonds have a fracture toughness less than 11 MPa·m1/2.

The invention

Thus, the present invention relates to a device and method for producing a diamond, which essentially eliminates one or more problems due to limitations and disadvantages of the prior art.

The aim of the present invention is a device and method for producing diamond in a system for chemical vapor deposition, microwave induced plasma, which has a high fracture toughness.

Additional features and advantages of the invention will be set forth in the following description and will be partially understood from the description or can be learned in the practical implementation of the invention. These objectives and other advantages of this invention will be realized and attained by the system, in particular, specified in the description and in the claims, and accompanying drawings.

To achieve these and other advantages and in accordance with the present invention, which is implemented and described in detail,monocrystalline diamond, grown by chemical vapor deposition, microwave induced plasma, has a hardness of 50-90 GPA and fracture toughness of 15-20 MPa·m1/2.

In another embodiment, the single crystal diamond has a crack 18-20 MPa·m1/2.

In accordance with another embodiment of the present invention is a method of growing single-crystal diamond includes placing the seed diamond in the holder and growing single-crystal diamond at a temperature of from about 1000°C to about 1100°C so that the single crystal diamond has a crack 11-20 MPa·m1/2.

It should be understood that both the foregoing General description and the subsequent detailed description are illustrative and explanatory and are intended for further explanation of the claimed invention.

Brief description of drawings

Accompanying drawings, which are included to provide further understanding of the invention and are included within this description and be part of it, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.

Figure 1 is a schematic depiction of the indenter for testing the hardness and fracture toughness of the diamond.

Figure 2 is a picture the of the grooves, made on CVD-grown in a microwave induced plasma monocrystalline diamond.

Figure 3 is a graph showing the hardness and the hardness of CVD-grown in a microwave induced plasma monocrystalline diamonds compared to natural diamonds are type IIa.

Figure 4 is a graph showing the hardness and the hardness of CVD-grown in a microwave induced plasma monocrystalline diamonds, which were obtained at different temperatures, compared to natural diamonds are type IIa.

A detailed description of the preferred options

Now reference is made to the detailed description of preferred embodiments of the present invention, the results of which are illustrated in the accompanying drawings.

CVD-grown in a microwave induced plasma monocrystalline diamond relating to this application, was grown using the device described in the patent application No. 10/288499, filed November 6, 2002, entitled "Apparatus and Method for Diamond Production", which is incorporated in this description by reference. In General, a seed crystal of diamond is placed in the holder, which moves the seed diamond/growing diamond as the diamond is grown. The authors of this application are also the authors of the patent application U.S. No. 10/288499.

CVD-grown the microwave induced plasma monocrystalline diamond c of a thickness exceeding 1 mm was deposited on the faces {100} of synthetic diamond type Ib. To increase the growth rate (50-150 μm/h) and activation of the smoothing process of growth faces {100} single-crystal diamonds grown in an atmosphere of N2/CH4=0.2 to 5.0% and CH4/H2=12-20% for total pressure 120-220 Torr and 900-1500°C from the microwave-induced plasma in the CVD chamber. Raman spectra showed the presence of small amounts of hydrogenated amorphous carbon (a-C:H)4and nitrogen-containing a-C:H(N:a-C:H)4resulting brown diamond at <950°C >1400°C. photoluminescence Spectrum (SF) indicated that impurities associated with nitrogen vacancy (N-V). Monocrystalline diamonds up to 4.5 mm were obtained when the growth rates of which the largest were two orders of magnitude higher than in conventional methods polycrystalline CVD growth.

Figure 1 is a schematic depiction of the indenter for testing hardness and trainerstation diamond. Determination of hardness by Vickers and trainerstation performed on annealed CVD-grown in a microwave induced plasma monocrystalline diamonds on the indenter 1, shown in figure 1. The indenter 1 figure 1 includes pressing material 2 placed on the holder 3. Pressing the substance 2 may be silicon carbide, diamond, or some other hard substance. Pressing the substance has the faces of the pyramids is through form, corresponding to the indenter Vickers, in which the parties pyramidal shape corresponding to the indenter Vickers, form an angle of 136°.

The indenter applies a point load to test the diamond 2 until, until there is formed a recess or a crack in the tested diamond 2. To prevent elastic deformation of the indenter, the goods range from 1 to 3 kg on the faces {100} in the direction <100> test diamonds. Figure 2 is an image of a hole made on CVD-grown microwave induced plasma monocrystalline diamond. The dimensions of the cavities and cracks associated with deepening, measured by optical microscopy.

Measuring the length D and the height h of the recess, the hardness of Hvexperienced diamond can be determined from the following equation (1):

where P is the maximum load used in the indenter for the formation of depressions in the tested diamond, D means the length of the longest cracks formed under the influence of indenter test the diamond, and h denotes the depth of the recesses in the tested diamond, as shown in figure 1.

The fracture toughness Kctest the diamond may be determined using a hardness of Hvfrom equation (1) by the following equation (2):

is the young's modulus, which is taken equal to 1000 HPa. P is the maximum load used in the indenter for the formation of depressions in the tested diamond. The value of d means the average length of the depression deepening of experience in the diamond, as shown in figure 2, such that d=(dl+d2)/2. The value of c means the average length of the radial cracks in the tested diamond, as shown in figure 2, such that c=(cl+c2)/2.

Figure 3 is a graph showing the hardness and the hardness of CVD-grown in a microwave induced plasma monocrystalline diamonds compared to natural diamonds are type IIa. CVD-grown in a microwave induced plasma, single crystal diamonds grown at temperatures of approximately 1300°to achieve high-speed growth. As shown in figure 3, the CVD-grown in a microwave induced plasma monocrystalline diamonds have a much higher crack resistance 6-18 MPa·m1/2than natural diamond type IIa. Most of the CVD-grown in a microwave induced plasma monocrystalline diamonds have a much higher crack resistance compared to the marked area values trainerstation for natural diamond type IIa, shown in the form of points selected rectangle 10 figure 3 and marked by the range trainose the stability for polycrystalline CVD diamond, shown as the highlighted points of the rectangle 20 figure 3. CVD-grown in a microwave induced plasma monocrystalline diamonds are presented on figure 3, have a crack 11-18 MPa·m1/2and a hardness of 50-90 GPA.

As installed, figure 3 presents the differences in trainerstation CVD-grown in a microwave induced plasma monocrystalline diamonds to some extent correlated with temperature processing. Accordingly, the authors of the present invention raised additional CVD-grown in a microwave induced plasma, monocrystalline diamonds within specific ranges of temperature treatment. In other words, a seed crystal of the diamond is placed in the holder and carried out the growth of single-crystal diamond within specific ranges of temperature treatment. These additional CVD-grown in a microwave induced plasma monocrystalline diamonds were then subjected to the same test for hardness and crack resistance.

Figure 4 is a graph showing the hardness and the hardness of CVD-grown in a microwave induced plasma monocrystalline diamonds, which were obtained at different temperatures, compared to natural diamonds are type IIa. More specifically, figure 4 shows twardoski hardness of CVD-grown in a microwave induced plasma monocrystalline diamond, which were respectively obtained at temperatures of more than 1300°at 1150-1250°and 1000-1100°C. As shown in figure 4, CVD-grown in a microwave induced plasma monocrystalline diamonds at 1000-1100°have a fracture toughness of about 18-20 MPa·m1/2and hardness 60-70 GPA.

Although the rate of growth of single-crystal diamond was reduced, single-crystal diamonds grown at 1000-1100°S, can be obtained with high crack resistance 18-20 MPa·m1/2. Unknown other synthetic or natural diamonds, which have such a high cracking resistance. In addition, diamonds grown at higher temperatures, such as 1150-1350°may not necessarily achieve high fracture toughness, but they tend to have high hardness, which makes these diamonds are useful for other purposes.

Since the present invention can be implemented in several forms of neustupny from the essence or essential features thereof, it should also be understood that the above options are not limited by any details of the above description, unless otherwise noted, and should be construed broadly within its essence and scope defined in the attached claims, and therefore assumes that all changes and mod the classification, included within the scope of the claims or the equivalent of such amount, included in the accompanying claims.

1. Single-crystal diamond grown by chemical deposition from the gas phase induced by microwave plasma having a hardness of 50-90 GPA and fracture toughness 11-20 MPa·m1/2.

2. Single-crystal diamond according to claim 1, where the crack is 18-20 MPa·m1/2.

3. Single-crystal diamond according to claim 1, where the hardness is 60-70 GPA.

4. Monocrystalline diamond with crack 18-20 MPa·m1/2.

5. Single-crystal diamond according to claim 4, having a hardness of 60-70 GPA.

6. A method of growing a single crystal diamond comprising placing the seed diamond in the holder; and growing a single crystal diamond by chemical deposition from the gas phase, microwave induced plasma, at a temperature of from about 1000°C to about 1100°C in an atmosphere of N2/CH4=0.2 to 5.0% and CH4/N2=12-20% for total pressure 120-220 Torr so that the single crystal diamond has a crack 11-20 MPa·m1/2.

7. The method according to claim 6, in which the growth of single-crystal diamond results in a single-crystal diamond, with a hardness of 60-70 GPA.



 

Same patents:

FIELD: carbon materials.

SUBSTANCE: monocrystalline diamond grown via chemical precipitation from gas phase induced by microwave plasma is subjected to annealing at pressures above 4.0 GPa and heating to temperature above 1500°C. Thus obtained diamonds exhibit hardness higher than 120 GPa and crack growth resistance 6-10 Mpa n1/2.

EFFECT: increased hardness of diamond product.

12 cl, 3 dwg, 5 ex

FIELD: crystal growth.

SUBSTANCE: method comprises separating the inoculation from the source of carbon by a metal-dissolver made of an alloy of ferrous, aluminum, and carbon when a 20-30°C temperature gradient is produced between the carbon source and inoculation. The growth zone is heated up to a temperature higher than the melting temperature of the alloy by 10-20°C, and the melt is allowed to stand at this temperature for 20 hours. The temperature then suddenly increases above the initial temperature by 10-25°C and decreases down to the initial value with a rate of 0.2-3 degree per minute.

EFFECT: improved quality of crystal.

1 tbl, 2 ex

FIELD: inorganic chemistry; mining industry; electronics; other industries; methods of the synthesis of the needle-shaped and lengthened diamonds.

SUBSTANCE: the invention is pertaining to the field of the inorganic chemistry, in particular, to the method of production of the needle shape synthetic diamonds and may be used in the industrial production of the special-purpose diamonds, for example, for manufacture of the boring crown bits and the dressers, and also in the capacity of the blocks details of the audio-video playback equipment, for manufacture of the feeler probes, in the micro-mechanical devices etc. The method provides for commixing of the fusion charge composed of the alloy of Mn-Ni-Fe in the mass ratio of 60±5÷30±5÷10±5 and the powder of the carbon-containing substance and treatment of the mixture at the pressure exceeding 40 kbar and the temperature over 950°С at heating rate less than 100°C/minutes. In the capacity of the carbon-containing substance use the needle-shaped coke or graphite on the coke basis with the single-component anisotropic structure with the degree of graphitization of no less than 0.55 relative units. The invention allows to simplify the production process of the synthesis of the needle-shaped and lengthened diamonds and to increase the percentage of their output within one cycle of the production process.

EFFECT: the invention ensures simplification of the production process of the synthesis of the needle-shaped and lengthened diamonds, the increased percentage of their output within one cycle of the production process.

2 ex, 2 dwg

FIELD: carbon materials.

SUBSTANCE: invention relates to preparation of boron-alloyed monocrystalline diamond layers via gas phase chemical precipitation, which can be used in electronics and as jewelry stone. The subject matter is uniformity of summary boron concentration in above-mentioned layer. The latter is formed in one growth sector and characterized by thickness above 100 μm and/or volume exceeding 1 mm3. Boron-alloyed monocrystalline diamond preparation involves diamond substrate provision step, said substrate having surface containing substantially no crystal lattice defects, initial boron source-containing gas preparation step, initial gas decomposition step, and the step comprising homoepitaxial growth of diamond on indicated surface containing substantially no crystal lattice defects.

EFFECT: enabled preparation of thick high-purity monocrystalline diamond layers exhibiting uniform and useful electronic properties.

44 cl, 5 tbl, 7 ex

FIELD: producing artificial diamonds.

SUBSTANCE: method comprises preparing diamond substrate virtually having no defects, preparing the initial gas, decomposing initial gas to produce the atmosphere for synthesis that nitrogen concentration of which ranges from 0.5 to 500 particles per million, and homogeneous epitaxy growth of diamond on the surface.

EFFECT: increased thickness of diamond.

40 cl, 9 dwg, 5 ex

FIELD: carbon particles.

SUBSTANCE: invention relates to technology of preparing particles having monocrystalline diamond structure via growing from vapor phase under plasma conditions. Method comprises step ensuring functioning of plasma chamber containing chemically active gas and at least one carbon compound and formation of reactive plasma, which initiate appearance of seed particles in the plasma chamber. These particles ensure multidirectional growing of diamond-structured carbon thereon so that particles containing growing diamond are formed. Functioning of plasma chamber proceeds under imponderability conditions but can also proceed under gravitation conditions. In latter case, seed particles and/or diamond-containing particles in reactive plasma are supported under effect of external gravitation-compensating forces, in particular by thermophoretic and/or optic forces. Temperature of electrons in the plasma are lowered by effecting control within the range from 0.09 to 3 ev. Chamber incorporates plasma generator to generate plasma with reduced electron temperature and device for controlling forces to compensate gravitation and to allow particles to levitate in the plasma with reduced electron temperature. This device comprises at least one levitation electrode for thermophoretic levitation of particles in plasma with reduced electron temperature or an optical forceps device.

EFFECT: enabled efficient growing of high-purity duly shaped particles with monocrystalline diamond structure having sizes from 50 μm to cm range (for instance, 3 cm).

19 cl, 5 dwg

FIELD: production of synthetic diamonds, which may be used as windows in high power lasers or as anvils in high pressure devices.

SUBSTANCE: device for forming a diamond in precipitation chamber contains heat-draining holder for holding a diamond and ensuring thermal contact with side surface of diamond, adjacent to the side of growth surface of diamond, non-contact temperature measurement device, positioned with possible measurement of diamond temperature from edge to edge of growth surface of diamond, and main device for controlling technological process for producing temperature measurement from non-contact device for measuring temperature and controlling temperature of growth surface in such a way, that all temperature gradients from edge to edge of growth surface are less than 20°C. A structure of sample holder for forming a diamond is also included. Method for forming a diamond includes placing a diamond in the holder in such a way, that thermal contact is realized with side surface of diamond, adjacent to growth surface side of diamond, measurement of temperature of growth surface of diamond, with the goal of realization of temperature measurements, control of growth surface temperature on basis of temperature measurements and growth of monocrystalline diamond by means of microwave plasma chemical precipitation from steam phase on growth surface, under which the speed of diamond growth exceeds 1 micrometer per hour.

EFFECT: possible production of sufficiently large high quality monocrystalline diamond with high growth speed.

7 cl, 1 tbl, 7 dwg

FIELD: chemical industry; cutting tool industry; mechanical engineering; methods of the production of the artificial highly rigid materials.

SUBSTANCE: the invention is pertaining to production of the artificial highly rigid materials, in particular, diamonds, and may be used in chemical industry; cutting tool industry; mechanical engineering, boring engineering. The method provides for compaction of the powdery carbon-containing materials in the field of the quasi-equilibrium state of the graphite-diamond system and the slow refrigeration in the zone of the thermodynamic stability of the diamond or other synthesized material. The heated capsule made out of tungsten with the pure carbon raw fill in with the liquid silicon at the temperature of 1750°K, hermetically plug up, then reduce the temperature to 1700°K during 30-40 minutes and cool to the room temperature within 5-6 hours in the process of the synthesis of the high-strength materials. The monocrystals of the boron carbide of the 400-450 microns fraction and the diamonds of the 40 microns fraction have been produced. The technical result of the invention consists in improvement of the quality, the increased sizes of the monocrystals, and also in the decreased labor input of the production process.

EFFECT: the invention ensures the improved quality and the increased sizes of the produced monocrystals, the decreased labor input of the production process.

2 cl, 2 ex

FIELD: treatment of diamonds.

SUBSTANCE: proposed method of change of diamond color includes the following stages: (i) forming reaction mass at presence of diamond in pressure-transmitting medium fully surrounds the diamond; (ii) subjecting the reaction mass to action of high temperature and pressure during required period of time; proposed diamond is brown diamond, type IIa; its color is changed from brown to colorless by subjecting the reaction mass to action of temperature of from 2200°C to 2600°C at pressure of 7.6 Gpa to 9 Gpa.

EFFECT: possibility of keeping diamond intact during treatment.

46 cl, 4 dwg, 1 ex

FIELD: treatment of diamonds.

SUBSTANCE: proposed method includes the following stages: (i) forming of reaction mass at presence of diamond in pressure-transmitting medium fully surrounding the diamond and (ii) action of reaction mass by high temperature and pressure during required period of time; diamond is of IIb type and its color is changed from gray to blue or dark blue or is enriched by action on reaction mass of temperature from 1800°C to 2600°C at pressure of from 6.7 GPa to 9 GPa (first version). Diamond of type II may be also proposed which contains boron and its color is changed to blue or dark blue by action on reaction mass by the same temperature and pressure (second version).

EFFECT: improved color of diamond by changing it from gray (brown-gray) to blue or dark blue.

31 cl, 4 dwg, 2 ex

FIELD: physics; microelectronics.

SUBSTANCE: device intended to produce layers from gas phase at reduced pressure that includes a deposition chamber composed of an inner reactor in the form of horizontal pipe with longitudinal holes in its walls arranged regularly in a checkered pattern, which is installed coaxially with outer reactor implemented as horizontal pipe to form with said inner reactor a chamber for gaseous chemical agents supply equipped with nipples for gaseous chemical agent injection, an evacuation system equipped with three vacuum gates, two of which located in the evacuation system of vacuum pump connected to the ends of said deposition chamber via evacuation chambers, and the third gate located between them symmetrically to the deposition chamber, and a heater. The gaseous chemical agent supply chamber is equipped with an additional nipple implemented in the form of evacuated quartz tube inserted to the middle of the gaseous chemical agent supply chamber, provided that outlet of the additional nipple is located between longitudinal holes of the inner reactor.

EFFECT: provision of isothermic and isobaric conditions of layer depositing; results in elimination of inhomogeneity of layer properties over depositing zone.

2 dwg

FIELD: physics; microelectronics.

SUBSTANCE: device intended to produce layers from gas phase at reduced pressure that includes a deposition chamber composed of an inner reactor in the form of horizontal pipe with longitudinal holes in its walls arranged regularly in a checkered pattern, which is installed coaxially with outer reactor implemented as horizontal pipe to form with said inner reactor a chamber for gaseous chemical agents supply equipped with nipples for gaseous chemical agent injection, an evacuation system equipped with three vacuum gates, two of which located in the evacuation system of vacuum pump connected to the ends of said deposition chamber via evacuation chambers, and the third gate located between them symmetrically to the deposition chamber, and a heater. The gaseous chemical agent supply chamber is equipped with an additional nipple implemented in the form of evacuated quartz tube inserted to the middle of the gaseous chemical agent supply chamber, provided that outlet of the additional nipple is located between longitudinal holes of the inner reactor.

EFFECT: provision of isothermic and isobaric conditions of layer depositing; results in elimination of inhomogeneity of layer properties over depositing zone.

2 dwg

FIELD: carbon materials.

SUBSTANCE: monocrystalline diamond grown via chemical precipitation from gas phase induced by microwave plasma is subjected to annealing at pressures above 4.0 GPa and heating to temperature above 1500°C. Thus obtained diamonds exhibit hardness higher than 120 GPa and crack growth resistance 6-10 Mpa n1/2.

EFFECT: increased hardness of diamond product.

12 cl, 3 dwg, 5 ex

FIELD: carbon materials.

SUBSTANCE: invention relates to preparation of boron-alloyed monocrystalline diamond layers via gas phase chemical precipitation, which can be used in electronics and as jewelry stone. The subject matter is uniformity of summary boron concentration in above-mentioned layer. The latter is formed in one growth sector and characterized by thickness above 100 μm and/or volume exceeding 1 mm3. Boron-alloyed monocrystalline diamond preparation involves diamond substrate provision step, said substrate having surface containing substantially no crystal lattice defects, initial boron source-containing gas preparation step, initial gas decomposition step, and the step comprising homoepitaxial growth of diamond on indicated surface containing substantially no crystal lattice defects.

EFFECT: enabled preparation of thick high-purity monocrystalline diamond layers exhibiting uniform and useful electronic properties.

44 cl, 5 tbl, 7 ex

FIELD: crystal growing.

SUBSTANCE: invention relates to technology of growing semiconductor materials on substrate through chemical reactions of reactive gases and can be used in semiconductor industry. Method involves supplying hydrogen chloride to container with gallium source followed by supplying gas mixture containing gaseous gallium chloride, ammonia, and carrying gas to the surface of substrate. To increase gallium nitride monocrystal growth rate and simultaneously improve quality of gallium nitride monocrystal, supplying hydrogen chloride to container with gallium source is accompanied with passing carrying gas to additional gallium source. Then, aforesaid gas mixture is passed to the surface of substrate. To prevent possibility of getting particles on growth surface and to increase stability of process parameters, temperature of container with gallium source, to which hydrogen chloride is supplied, is maintained above 700°C, temperature of additional gallium source is maintained from 1100 to 1400°C, and temperature of gas phase in reactor as well as reactor wall temperature are maintained by 100-200°C higher then substrate temperature.

EFFECT: accelerated crystal growth and improved quality of monocrystals.

3 dwg

FIELD: crystal growing and semiconductor materials.

SUBSTANCE: invention relates to technology of manufacturing semiconductor materials and devices via gas epitaxy technique from organometallic compounds, in particular to manufacturing heterostructures based on group III element nitrides and devices utilizing the same, such as white light diodes, lasers, etc. Method of growing nonpolar epitaxial heterostructures for white light-emitting diodes based on compounds and solid solutions of group III element nitrides comprises gas-phase precipitation of one or more layers of heterostructures represented by formula AlxCa1-xN, where 0<x≤1, on substrate, which is a-langacite a-La3Ga5SiO14, with disagreement of c-parameters of lattice "substrate-epitaxial layer AlxCa1-xN" not exceeding the value within a range from -2.3% at x=1 to +1.7% at x=0 and disagreement of thermal expansion coefficient in direction of c-axis not exceeding the value within a range from +49% at x=1 to -11% at x=0.

EFFECT: enabled preparation of heterostructures with low density of defects and mechanical tensions.

6 cl, 4 dwg, 1 tbl

FIELD: producing artificial diamonds.

SUBSTANCE: method comprises preparing diamond substrate virtually having no defects, preparing the initial gas, decomposing initial gas to produce the atmosphere for synthesis that nitrogen concentration of which ranges from 0.5 to 500 particles per million, and homogeneous epitaxy growth of diamond on the surface.

EFFECT: increased thickness of diamond.

40 cl, 9 dwg, 5 ex

FIELD: producing artificial diamonds.

SUBSTANCE: method comprises preparing diamond substrate virtually having no defects, preparing the initial gas, decomposing initial gas to produce the atmosphere for synthesis that nitrogen concentration of which ranges from 0.5 to 500 particles per million, and homogeneous epitaxy growth of diamond on the surface.

EFFECT: increased thickness of diamond.

40 cl, 9 dwg, 5 ex

FIELD: optical electronics and crystal growing.

SUBSTANCE: invention relates to three-dimensional nitride monocrystal, in particular the one destined for use as support for epitaxy suitable for use in optoelectronics to manufacture optoelectronic semiconductor nitride-based devices and, more particular, to manufacture semiconductor laser diodes and laser devices. Invention discloses three-dimensional nitride monocrystal, namely gallium nitride monocrystal having surface area of cross-section in the plane perpendicular to c-axis of hexagonal crystal lattice of gallium nitride monocrystal larger than 100 mm2, thickness more than 1.0 μm, and surface dislocation density in plane C less than 106/cm2, while its volume is great enough to obtain at least one plate appropriate for further treatment, plane A or plane M of the plate having surface area at least 100 mm2. In a more general case, invention iscloses three-dimensional nitride monocrystal, namely nitride monocrystal containing gallium, which has cross-section in the plane perpendicular to c-axis of hexagonal crystal lattice of gallium-containing nitride with surface area larger than 100 mm2, thickness more than 1.0 μm, and surface dislocation density in plane C less than 106/cm2. These three-dimensional gallium-containing nitride monocrystals are crystallized using a method comprising dissolution of initial gallium-containing material in overcritical solvent and crystallization of gallium nitride on the surface of seed crystal at temperature higher and/or at pressure lower than those utilized in dissolution process.

EFFECT: improved quality of monocrystals due to reduced dislocation density.

48 cl, 20 dwg, 26 ex

FIELD: carbon particles.

SUBSTANCE: invention relates to technology of preparing particles having monocrystalline diamond structure via growing from vapor phase under plasma conditions. Method comprises step ensuring functioning of plasma chamber containing chemically active gas and at least one carbon compound and formation of reactive plasma, which initiate appearance of seed particles in the plasma chamber. These particles ensure multidirectional growing of diamond-structured carbon thereon so that particles containing growing diamond are formed. Functioning of plasma chamber proceeds under imponderability conditions but can also proceed under gravitation conditions. In latter case, seed particles and/or diamond-containing particles in reactive plasma are supported under effect of external gravitation-compensating forces, in particular by thermophoretic and/or optic forces. Temperature of electrons in the plasma are lowered by effecting control within the range from 0.09 to 3 ev. Chamber incorporates plasma generator to generate plasma with reduced electron temperature and device for controlling forces to compensate gravitation and to allow particles to levitate in the plasma with reduced electron temperature. This device comprises at least one levitation electrode for thermophoretic levitation of particles in plasma with reduced electron temperature or an optical forceps device.

EFFECT: enabled efficient growing of high-purity duly shaped particles with monocrystalline diamond structure having sizes from 50 μm to cm range (for instance, 3 cm).

19 cl, 5 dwg

FIELD: blasting operations.

SUBSTANCE: explosion chamber contains cylindrical hull, plain bottom, cover and fastening tools for charge of explosive substance inside the chamber, installed in cooling casing. The vertical hull and the chamber bottom is faced by steel of reinforced concrete, and as cooling casing it is used the water, partly filling the internal chamber volume, on the chamber bottom it is fixed the perforated tubes, connected with gas system or with water pump, on the inside hull surface it is fixed the vertical splitter of the air-blast wave with rectangular section, connected by several steel rings, the hull is provided with hatch, which is opened inside the chamber, nipples for gas and water excluding from the chamber and nipples for gas feeding to perforated tubes, the hatch is steel hermetical cistern filled with the water, which has nipples for water and water feeding, and also nipples for water feeding from cistern to the chamber, which are made as curved tubes, that the curve is situated higher then the water level in the cistern.

EFFECT: it is exceeded the productivity of the chamber as well as the convenience of using without stuff entering inside.

4 cl, 2 dwg

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