Method of producing large-size gallium antimonide monocrystals

FIELD: chemistry.

SUBSTANCE: invention relates to production of semiconductor materials and specifically to production of gallium antimonide monocrystals, which are used as substrate material in isoperiodic heterostructures based on ternary or quaternary solid solutions in Al-Ga-As-Sb and In-Ga-As-Sb systems, which enable to produce a wide range of optoelectronic devices (radiation sources and detectors in the 1.3-2.5 mcm spectral range). The method includes synthesis and growing a monocrystal using a Chochralski method in a hydrogen atmosphere on a seed crystal in the [100] crystallographic direction, wherein synthesis of the monocrystal is carried out in a single process with the flow rate of especially pure hydrogen in the range of 80-100 l/h and holding the melt at the synthesis step at 930-940°C for 35-40 minutes.

EFFECT: invention enables to obtain perfect large-size gallium antimonide monocrystals with diameter of 60-65 mm.

1 tbl

 

The invention relates to the field of production of semiconductor materials, namely, to obtain single crystals of gallium antimonide, which are used as base material in isoperiodic heterostructures based ternary and Quaternary solid solutions in the systems Al-Ga-As-Sb and In-Ga-As-Sb, which allows you to create a wide range of optoelectronic devices (sources and detectors of radiation in the spectral range of 1.3-2.5 μm).

The General trend of development of technologies of production of devices based on these structures is the transition matrix to execution. Consequently, there is a need of using single crystals of larger diameter while maintaining the stringent requirements for perfection patterns. Typically, when creating isoperiodic heterostructures Al-Ga-As-Sb and In-Ga-As-Sb as the element base plates are used GaSb working with orientation (100).

The technical problem solved by this invention is the creation of energy - saving method of obtaining large single crystals of gallium antimonide grown in the crystallographic direction [100].

There is a method of obtaining three-dimensional crystals of gallium antimonide-rich gallium melts using an additional source of gallium antimonide. The proposed method EN is a logical well-known in the practice of obtaining semiconductor materials a method of growing single crystals of the double crucible, used, typically, to obtain the highly doped crystals, with a coefficient of impurity distribution that is significantly different from one.

In the proposed method, according to the authors, the stability conditions of crystal growth is achieved through the use of the double crucible (growth and source), the design of which is a communicating vessels, which helps to maintain the constancy of the stoichiometric composition of the melt in the growing crucible (Akiyoshi Watanabe, Tanaka Akira, Sukegawa Tokuzo, /Journal of Crystal Growth, 128 (1-4), p.462-465, Mar 1993).

The disadvantage of this method is almost the impossibility of obtaining perfect single crystal due to the presence of a large number of twins. Therefore, this method can be recommended for obtaining large, with a high degree of homogeneity, polycrystalline material, which can be the feedstock for subsequent single crystal growth.

A method of obtaining single crystals of compounds And3In5by the Czochralski method with a liquid sealing of the melt using a flux2About3.The advantage of this method is the use of a special device that allows to maintain the stoichiometry of the melt during the whole process of getting through the regulation of the evaporation of the volatile component. Uh what about a very important condition for obtaining all semiconductor compounds, but the most important for compounds with high vapor volatile component in the melting point, to which the GaSb does not apply [U.S. patent No. 5256381, SW 35/00 (CDD 117/213, publ. 26.10.1993).

The disadvantage of this method is the use of flux In2About3; which due to the high dynamic viscosity at the melting point of gallium antimonide(706°C) is unsuitable for obtaining single crystals of this compound, which is one of the most low temperature in the range of connections And3In5. In addition, the regulation of the evaporation of antimony is very complicated, and, in our opinion, can be implemented using a simpler technical solutions.

A method of obtaining unalloyed and alloyed with tellurium single crystals of gallium antimonide by the Czochralski method in the crystallographic directions [100] and [111] of 50 mm diameter and weight of 600-1000 g in an atmosphere of pure hydrogen. The advantage of this method is the use of the device to get rid of the slag formations on the surface of the melt in the synthesis process. [A novel technique for Czochralski growth of GaSb single crystals. Mo, P.G.; Tan, H.Z.; Du, L.X.; Fan, X.Q./ Journal of Crystal Growth, 126 (4), p.613-616, Feb 1993]. This method of creating was selected as a prototype.

The disadvantages of this method is extremely complicated system of cleaning the melt, as well as a limited amount of download source components up to 1 kg, it is not possible to grow single crystals with a diameter of more than 5, see also, apparently, the method involves the use of a static atmosphere of hydrogen that ethnologica and cannot provide the mirror surface of the melt during the growth process. The consequence of this is the presence of a large number of twins in the grown ingots, which significantly reduces the yield of single-crystal material.

The technical result of the invention is:

- obtaining the perfect single crystals of gallium antimonide in the crystallographic direction [100], which reduces the loss of material when cutting an ingot on demand by the manufacturers of the devices plate with a similar orientation;

the decrease in the density of dislocations in large single crystals of gallium antimonide in determining the quality and effectiveness of the established on the basis of this material instruments;

- reduce energy, material and labor costs of the process of obtaining.

The technical result is achieved in that in the method of obtaining large single crystals of gallium antimonide, including the synthesis and growth of single crystal by the Czochralski method in a hydrogen atmosphere on a seed crystal, oriented in the crystallographic direction [00], according to the invention the synthesis and preparation of the single crystal is carried out in a single process with a speed of flow of highly pure hydrogen in the range of 80-100 l/h and the dwell time of the melt at the stage of synthesis at a temperature of 930-940°C for 35-40 minutes

The essence of the proposed method is that, instead of time-consuming and energy-consuming process of synthesis, purification and homogenization of polycrystalline ingot, the process of synthesis and preparation of the single crystal is carried out in a single technological cycle by Czochralski method. The claimed process conditions for the synthesis and single crystal growth of gallium antimonide provide the material with the required parameters and minimal losses.

During the process of synthesis of the changing of the requested modes, namely the increase or decrease in the stated velocity of the flow of highly pure hydrogen in the growth process, violates the conditions of obtaining a single crystal of stoichiometric composition.

Lowering the synthesis temperature to a temperature below 930°C does not allow to achieve the desired degree of homogenization and undergo a chemical reaction at the optimum time. Temperature increase to a temperature above 940°C is not rational because of the increased evaporation of antimony and violations of the stoichiometry of the melt.

Reducing or increasing the exposure time dissolved, and the awa violates the conditions of the process and does not allow you to grow a large single crystal with high perfection of the structure.

An example of the method.

To obtain a single crystal of gallium antimonide source components gallium and antimony (purity 6N) in the stoichiometric ratio, providing an excess of antimony in the range of 1-2 at.%, to prevent evaporation during the synthesis process and the growing load in the filter crucible installed in a working furnace crucible for growing crystals by the Czochralski method. After evacuating the furnace to 1.10-3mm Hg in the camera serves a highly pure hydrogen with a dew point (-65)+-(-70)°C and a flow rate of 80-100 l/h. Source components (Ga and Sb) is melted at a temperature of 930-940°C and maintained at the melt within 35-40 minutes followed by filtration of the melt in the working crucible through a hole in the bottom of the filtering crucible, thus there is an additional cleaning of the melt from random impurities and oxide formations remaining on the walls of the filtering crucible. Weight passing synthesis (homogenization of the melt in such a short time is provided by the intensity of mixing of the molten components by passing them through a hole in a filtering crucible. Reducing the temperature of the melt in the working crucible to a temperature close to the temperature of crystallization of gallium antimonide (706°C), hold the growing single crystal on a seed crystal with the crystallographic orientatie the [100] with a speed of 3-3,5 cm/hour with rotation of the crucible and the seed crystal in opposite directions with speeds of 10-12 rpm and 20-25 rpm, respectively.

The claimed flow rate of hydrogen 80-100 l/h following reason. During the process of growing with speeds of flow of hydrogen over 100 l/h increases sharply ash antimony from the melt, which leads to violation of its stoichiometry, crash, single-crystal growth and increase the proportion of non-stoichiometric part of the ingot up to 35-40%. In addition, the increase in the velocity of the flow of hydrogen affects the hydrodynamics of the heat flow in the chamber and thereby impairs the structural and plastic properties of as-grown ingots.

The process of growing with duct velocities of hydrogen less than 80 l/h does not provide the necessary clean the surface of the melt and promotes the violation of the smoothness of the crystallization front. The result is the failure of single-crystal growth and, consequently, increasing the share of non-stoichiometric part of the ingot by 30-35%.

Lowering the synthesis temperature to a temperature below 930°C does not allow to achieve the required homogenization of the melt to complete the synthesis, resulting in the inclusion of the second phase in the grown ingots, as well as the increase in non-stoichiometric part of the ingot up to 30%

Increasing the synthesis temperature to a temperature above 940°C resulted in a significant loss of volatile component in the Sb, respectively violation stachion the tree of the melt, that also increased the proportion of non-stoichiometric part of the ingot up to 25-30%.

The process of synthesis of gallium antimonide from the original components with the addition of an excess of Sb and exposure of the melt in the course of 45 min was accompanied by significant twinning on the solidification front at the stage seeding crystal, and also increased the proportion of non-stoichiometric part of the grown ingot by more than 20%. This is due to a violation of the stoichiometry of the melt by evaporation of antimony by increasing the duration of temperature exposure.

The process of synthesis of gallium antimonide from the original components with the addition of an excess of Sb and exposure of the melt within 25 min did not provide the desired degree of homogenization of the melt and completeness of the completion of the synthesis. Accordingly, the share of non-stoichiometric part in the grown ingot increased by about 30% and, in addition, in the grown ingot was observed microinclusions of the second phase.

Subject time 35-40 minutes at a temperature of 930-940°With the share of non-stoichiometric material was minimal and amounted to no more than 5% of the total weight of the ingot.

The proposed method under the present conditions of the growth process, namely: the dwell time of the melt at a temperature of 930-940°C for 35-40 minutes in a hydrogen atmosphere with a flow rate 80-10 l/h was 3 grown undoped single crystal of gallium antimonide 60-65 mm in diameter and 4 doped with tellurium single crystal of gallium antimonide 60-65 mm in diameter with a crystallographic orientation of [100].

On plates with orientation (100), carved from the start and end parts of the bars perpendicular to the growth axis, and control of electrophysical parameters of the obtained single crystals: the concentration and mobility of the main charge carriers. Identification of dislocation and defect structure of the obtained single crystals of gallium antimonide were performed on the same plate using selective etching to provide the Etchant composition model HC1:H2About2=2:1 for 1 min [V.T. Bublik, Smirnov V.M., Milwidsky A.G. crystallography 37, 1992, No. 2. P.56-61]. Structural features of the obtained single crystals were investigated using optical microscopy. As samples were used for comparison of the single crystals of gallium antimonide with a diameter of 40 mm, grown by the standard technology in the crystallographic direction<211>.

Table 1 presents the electrophysical parameters and values in the dislocation density obtained by the above method single crystals of gallium antimonide.

The results obtained indicate that the values of electrophysical parameters of large non-alloy and alloy (Te) single crystals of gallium antimonide grown in the crystallographic direction [100], are at the level of values for these parameters, in which monokristallakh GaSb diameter up to 40 mm As evidenced by the results shown in table 1, according to its structural perfection of large single crystals of gallium antimonide with a diameter up to 65 mm, grown in the crystallographic direction [100], is much higher than the single crystals of gallium antimonide received earlier in the crystallographic direction [211] on THE other, the diameter of which does not exceed 40 mm, and the dislocation density is not less than 1-5·104cm-2. It should also be noted that the distribution of the dislocation density on diameter wafers with orientation (100) is much more evenly than on plates with orientation (211), in which this distribution is W-shaped character. The latter circumstance is extremely important for materials used as the substrate, so as to a large extent determines the perfection stackable epitaxial layers.

Thus, the claimed invention allows to:

1. Due to the improvement of the cultivation process in compliance with the proposed conditions and exclusions stage of the polycrystalline material, which is the source for subsequent single crystal growth, significantly reduce energy and resource consumption of the process and work that characterize this process.

Alocit structure of the obtained single crystals with simultaneous increase is receiving their diameter up to 65 mm, namely, to reduce the average value of the dislocation density and to improve uniformity of their distribution in the crystal as a factor that defines the parameters generated on the basis of sinks and sources of radiation.

3. increase the powers yield plates for cutting ingots due to the fact that the direction of growing a single crystal [100] coincides with the working orientation of the wafer (100)is used as base material in isoperiodic heterostructures based ternary and Quaternary solid solutions in the systems Al-Ga-As-Sb and In-Ga-As-Sb, which allows you to create a wide range of optoelectronic devices (sources and detectors of radiation in the spectral range of 1.3-2.5 μm).

The method of obtaining large single crystals of gallium antimonide, including the synthesis and growth of single crystal by the Czochralski method in a hydrogen atmosphere on a seed crystal, oriented in the crystallographic direction [100], characterized in that the synthesis and preparation of the single crystal is carried out in a single process with a speed of flow of highly pure hydrogen in the range of 80-100 l/hour and holding time of the melt at the stage of synthesis at a temperature of 930-940°C for 35-40 minutes



 

Same patents:

FIELD: electrical engineering.

SUBSTANCE: for production of coarse-grain indium ammonide monocrystals oriented in the crystallographic direction [100] one performs synthesis and production of a polycrystal coarse-grain ingot by way of a combined process according to the Czochralski method with addition of an amount of stibium in excess of the stoichiometric 3.0-3.5 at %; then one performs monocrystal growth (equally according to the Czochralski method) using a seed crystal oriented in a crystallographic direction [100], the axial temperature gradients maintained as equal to 35-40 grad/cm.

EFFECT: invention enables improvement of crystals structure with simultaneous increase of their diameter up to 70,2 mm, increase of mountain plates yield during ingot cutting due to the growth direction, reduction of the process material intensity due to reduction of the share of non-stoichiometric material and reduction of energy and labour costs due to usage of a combined process of polycrystal ingot synthesis, cleaning and growing.

1 tbl, 1 ex

FIELD: chemistry.

SUBSTANCE: invention relates to manganese- and zinc-doped indium antimonides which can be used in spintronics, where electron spin is used as an active element for storing and transmitting information, forming integrated and microfunctional circuits, as well as designing novel magneto-optoelectronic devices. A magnetic semiconductor material is disclosed, which contains indium, antimony, manganese and zinc, and is indium antimonide InSb doped with manganese in amount of 0.12-0.19 wt % Mn and zinc in amount of 0.71-1.12 wt % Zn, and has the formula InSb<Mn,Zn>.

EFFECT: invention enables to obtain material which is characterised by Curie point of 320 K and combines semiconductor and ferromagnetic properties.

2 dwg, 2 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: method involves seeding, growing a monocrystal to given diameter while simultaneously stretching its conical part at a given rate and then growing the cylindrical part of the crystal. When growing the conical part of the monocrystal, the speed of rotation of the crucible and the rate of stretching the monocrystal are respectively increased from 0-2 rpm and 0-5 mm/h while seeding to 3-6 rpm and 15-30 mm/h upon achieving the given diameter, and after achieving the given diameter, the rate of stretching the conical part of the monocrystal is increased to 50-150 mm/min for 1.0-6.0 s, followed by continued growth of the cylindrical part of the monocrystal at a given rate. The seed crystal can have crystal-lattice orientation of the growing axis of <511>B.

EFFECT: reduced probability of twinning on the conical part of the monocrystal owing to high quality and higher output of suitable indium phosphide monocrystals.

2 cl, 1 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention can be used in production of monocrystals of decomposable semiconductor compounds A3B5 via Czochralski method, particularly when growing monocrystals of phosphides of gallium and indium and gallium arsenide from under a boric anhydride layer. A3B5 monocrystals are obtained by drawing from melt to a nucleating agent under a boric anhydride layer which is loaded into a container, heated and melted. Molten boric anhydride is held for 0.5-3 hours at 900-1200°C with axial temperature gradient of 5-40°C/cm and addition of gallium in amount of 0.8-3.0 % of the weight of boric anhydride. Sullage is removed from the surface of the melt and volatile impurities are removed through ventilation. Vacuum pumping is then carried out for 0.5-20 hours at 950-1250°C. Boric anhydride is removed from the container and cooled. Addition of bismuth in amount of 0.01-0.5% of the weight of boric anhydride is proposed when melting boric anhydride together with gallium. Boric anhydride can be obtained by using boric acid, a portion of which is put into a container in amount of 10-20% of the load weight and dehydrated. Gallium is then added in amount of 0.4-1.5% of the weight of boric acid, after which the remaining portion of boric acid and molten boric anhydride is held for 0.5-2 hours before vacuum pumping. When removing boric anhydride from the container, all the gallium and a portion of boric anhydride in amount of 50-300% of the weight of the initial gallium can be left. Boric anhydride is then loaded again and the process is repeated. The obtained boric anhydride and A3B5 compound are loaded into a crucible and heated and a monocrystal is grown on a nucleating agent from the melt.

EFFECT: high output of suitable and improved quality of monocrystals for optical devices and production of ultra bright light-emitting diodes owing to lower content of impurities in the boric anhydride and molten A3B5 compound.

4 cl, 3 ex, 2 tbl

FIELD: metallurgy, crystal growing.

SUBSTANCE: invention refers to semi-conductor technology of AIIIBV type compositions. The method is implemented by means of bombarding mono-crystalline plates of arsenide-indium with fast neutrons with following heating, annealing and cooling. The mono-crystalline plates are subject to bombardment with various degree of compensation at density of flow not more, than 1012 cm-2 c-1 till fluence F=(0.5÷5.0)·1015 cm-2 , while annealing is carried out at 850÷900°C during 20 minutes at the rate of heating and cooling 10 deg/min and 5 deg/min correspondingly.

EFFECT: production of arsenide-iridium plate with upgraded uniformity and thermal-stability of electro-physical characteristics and with decreased degree of compensation.

2 ex, 1 tbl

FIELD: metallurgy, crystal growing.

SUBSTANCE: invention refers to process of production of AIIIBV semi-conducting compositions. Mono-crystals of indium antimonide alloyed with tin are produced by means of bombardment with a full specter of reactor neutrons with successive heating, annealing and cooling. Heating is carried out at the rate of 20÷40 deg/min to temperature of annealing, defined by the formula Tanneal=450+(tgNsn-14)-7 [°C], where Nsn is concentration of introduced alloying addition of tin [cm-3]; annealing is performed during 20 minutes, while the successive cooling is carried out at the rate of 5-10 deg/min to the temperature of 350÷400°C, and further at the rate of 20-40 deg/min to an ambient temperature.

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2 ex, 1 tbl

FIELD: metallurgy, crystal growth.

SUBSTANCE: invention refers to single crystals growth by the method of vertical directed crystallisation and can be used in single crystal growth technology for semiconductors with a purpose of producing bulk single crystals of a high grade of structure perfection. The method includes crystallisation of melt in a crucible on a inoculating crystal placed in the lower portion of the crucible and having an area of cross section much less than an area of the main section of the crucible. As an inoculating crystal a single crystal is used wherein lines of dislocation are situated predominantly at an angle of 45 degrees to vertical and more; further as an inoculating crystal there can be used a single crystal, containing an isovalent alloying additive with a concentration of above 1018 atom/cm3.

EFFECT: reduction in dislocation density in grown single crystals and correspondingly the result is upgraded quality of singly crystals of a large diameter.

2 cl, 3 ex, 1 dwg

FIELD: chemical industry; semi-conductors industry; other industries; devices for feeding of the gallium chloride vapors at the gas-phase deposition of the А3В5 compounds.

SUBSTANCE: the invention is pertaining to production of the А3В5 semi-conducting compounds used for manufacture of the substrates based on GaN, GaAs, GaP, etc. The device for feeding of the gallium chloride vapors at the gas-phase deposition of the А3В5 compounds contains two tanks connected among themselves, one of which is intended for storage of gallium chloride, and the other - for batching of the gallium chloride vapors into the deposition zone by the stream of the gas-carrier. The device contains the thermostat, in which the indicated tanks are located. At that the tank for batching is rigidly fixed in it, and the tank for storage is tightened with the capability of relocation in the vertical direction concerning the batching tank. The tanks contain the upper and side fitting pipes for the gas-carrier inlet and outlet accordingly. At that the side fitting pipe of the storage tank is connected with the upper fitting pipe of the batching tank, and the lower fitting pipes used for relocation of the liquid gallium chloride from one tank into another tank connected among themselves. All the joints are executed by the flexible pipelines. The thermostat is placed on the stand with the capability of turning by 90 degrees round the horizontal axis coinciding with the axis of the inlet fitting pipe of the storage tank and with the axis of the outlet fitting pipe of the batching tank. The device ensures production of the massive (with the thickness exceeding 1 mm) layers of the А3В5 compounds with the preset characteristics (the thickness, the composition, etc.) at the expense of maintaining of the constant concentration of the gallium chloride in the gas-carrier to the extent of its consumption in the process of growing of the layers.

EFFECT: the invention ensures production of the massive with the thickness exceeding 1 mm layers of the А3В5 compounds with the preset characteristics of the thickness, the composition and others due to maintaining of the constant concentration of the gallium chloride in the gas-carrier to the extent of its consumption in the process of growing of the layers.

1 dwg

The invention relates to the technology of semiconductor materials and can be used to create optoelectronic devices operating in the spectral range of 0.59-of 0.87 μm

FIELD: physics, optics.

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EFFECT: invention increases the size of obtained crystals.

10 cl, 9 dwg, 4 ex

FIELD: metallurgy.

SUBSTANCE: invention relates to production of silicon monocrystals by Czochralski method or silicon multicrystals by method of directed crystallisation to be used in making solar cells and modules with higher operating performances. Proposed method comprises preparing initial mix alloyed with boron and its melting. Note here that aluminium is added to produced melt in amount sufficient for allow ratio between concentrations of aluminium and oxygen equal to 1-102.

EFFECT: p-type conductance silicon with low concentration of oxygen.

1 ex

FIELD: metallurgy.

SUBSTANCE: invention relates to the technology of growing monocrystals using Chokhralsky method. Growth of doped crystals of lithium niobate with composition close to stoichiometric is done on an inoculating crystal from molten mixture of lithium niobate of identical composition with ratio Li/Nb equal to 0.938-0.946 and containing 9-13 mol % K2O and 0.5-2.5 mol % MgO or ZnO, in conditions of applied electric field with current density of 0.2-40 A/m2. A device is provided for realising the method, comprising a housing with a growth station and a cooling chamber, crucible 1, placed in the growth station, induction heater, top metallic heating shield 4, fitted above the crucible 1, mechanism for moving the crystal with a coupling rod, a rod with a holder 3 for the inoculating crystal 2. The device is also provided with a regulated direct current source 10 with electrodes; under the inoculating crystal 2 there is an additional load from electrically conducting material, separated from the wall of the holder by electrically insulating material. One of the electrodes is connected to the crucible 1, and the second - to the load.

EFFECT: invention allows for growing large optically homogenous crystals of lithium niobate with composition close to stoichiometric Li/Nb>0,994, additionally doped with MgO or ZnO, composition of which in the top and bottom parts of the crystal is virtually the same, without destroying the inoculating crystal.

5 cl, 2 ex, 2 dwg

FIELD: technological process.

SUBSTANCE: invention is related to growing of garnets single crystals and may be used in laser equipment, magnet microelectronics (semi-conductors, ferroelectrics) and for jewelry purposes. Single crystals of terbium-gallium garnet are prepared by Chochralski method by means of melting primary stock, which includes clarifying calcium-containing additive, and further growing of single crystal from melt to primer. As primary stock mixture of terbium and gallium oxides is used, as calcium containing additive - calcium oxide or carbonate, and after growing crystal is annealed in atmosphere of hydrogen at temperature of 850-950°C for around 5 hours until orange paint disappears.

EFFECT: allows to prepare optically transparent homogeneous crystals.

2 ex

FIELD: chemistry; passive Q-switch crystal growing process.

SUBSTANCE: production process for growing crystals of galium scandium gadolinium garnets is based on Czochralski process, which implies crystal growing from initial molten batch, which is congruently melting gallium scandium gadolinium garnet produced by 3-phase synthesis, doped with magnesium oxide and chromium oxide. These oxides provide for 2.0×1020-2.6×1020 atoms/cm3 concentration of cromium and magensium cations in melt during the first crystal growing, in argon with 14-17% of carbon dioxide, pressure in chamber being 1.3-2.0 atm. For the second, third and subsequent growths, an initial batch amount equal to previous crystal weight, cromium and magnesium content in batch being determined according to formula (СCr×СMg)/1020 = 0.5÷2, where СCr is at least 5×1019 atoms/cm3, is added to the crucible.

EFFECT: provides for required Q-switched mode, continuous or pulse, within wavelength range of 1,057-1,067 mcm.

2 ex

FIELD: crystal growing technologies.

SUBSTANCE: invention relates to technology of growing crystals for passive laser shutters used in modern lasers operated in IR spectrum region. Crystals are grown according to Chokhralsky method from initial stock melt containing metal oxide mixture, namely produced via solid-phase synthesis gallium-scandium-gadolinium garnet of congruently melting composition with magnesium and chromium oxide additives assuring concentration of chromium and magnesium cations in melt 2.0·1020 to 2.6·1020 at/cm3. Process is carried out at cell pressure 1.4 atm in argon and carbon dioxide medium with carbon dioxide content 14-17% by volume. Invention makes it possible to grow perfect crystals of gallium-scandium-gadolinium garnets alloyed with chromium cations, which are characterized by absorption coefficient above 5 cm-1 within wavelength 1.057-1.067 μm generation range.

EFFECT: achieved required Q-switching mode in continuous and pulsed operation conditions.

6 ex

FIELD: production of solar batteries, integrated circuits and other semiconducting devices.

SUBSTANCE: the invention presents a method of production of alloyed monocrystals or polycrystals of silicon and may be used in production of solar batteries, integrated circuits and other semiconductor devices. The substance of the invention: the method of SUBSTANCE: the invention presents a method of production of alloyed monocrystals or polycrystals of silicon includes preparation of the initial charge consisting of 50 % of silicon alloyed with phosphorus with a specific electrical resistance of 0.8-3.0 Ohm·cm or boron with specific electrical resistance of 1-7 Ohm·cm, its melting-down and consequent growing of crystals from the melt, in which additionally enter elements of IV group from the periodic table by Mendeleyev, in the capacity of which use germanium, titanium, zirconium or hafnium use in concentrations of 1017-7·1019 cm-3. The invention allows to produce chips with high values of life time of minority carrier (LTMC), high homogeneity of electric resistivity (ER) and high concentration of oxygen, with a low concentration of defects and increased thermostability and radiation resistance.

EFFECT: the invention ensures production of chips with high values of LTMC, high homogeneity of ER and high concentration of oxygen, with a low concentration of defects and increased thermostability and radiation resistance.

2 cl, 4 ex, 1 tbl

FIELD: crystal growth.

SUBSTANCE: method comprises crystal growing in two stages: growing alloyed crystals used for making blanks of seeds made of a disk of a given diameter and approximately 5-6-mm thick and subsequent growing of nominally pure crystals.

EFFECT: enhanced quality of crystals.

3 dwg

The invention relates to methods of obtaining crystals, namely the method of producing single crystals of lutetium-yttrium aluminate, and can be used in the manufacture of scintillation elements used in the detectors of ionizing radiation in medical diagnostic equipment

The invention relates to the production of semiconductor ingots and wafers, in particular silicon crystals with cyclic twinned structure

FIELD: chemistry.

SUBSTANCE: germanium monocrystals are grown in crystallographic direction [111] after holding at melting point for 1-2 hours, with temperature gradient at the crystallisation front in the range of (10.0÷18.0) K/cm, which provides dislocation density on the level of (2·104-5·105) per cm2.

EFFECT: invention enables to obtain germanium monocrystals with considerable increase in signal reception area due to directed introduction of a given concentration of dislocations into the grown crystal and conversion of said dislocations from standard crystal defects to active elements of infrared optical devices.

3 dwg, 1 tbl

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