307results about "Under a protective fluid" patented technology

The invention relates to the technical field of photovoltaic crystal growth, in particular to a method for improving the axial resistance uniformity of an antimony-doped silicon single crystal and the antimony-doped silicon single crystal. The method provided by the invention comprises the following steps: growing the antimony-doped silicon single crystal by adopting a czochralski method, and at an equal-diameter stage, controlling the furnace pressure to be 4-13torr; in the czochralski method, after leading and releasing are failed or growth of a single antimony-doped silicon single crystal is completed, supplemental doping of an antimony element is carried out according to the volatilization amount of the antimony element. In the method disclosed by the invention, the tail resistance and the head resistance of the prepared antimony-doped silicon single crystal are kept highly consistent by controlling the furnace pressure at the equal-diameter stage, regulating and controlling the volatilization rate of the antimony element, combining the segregation phenomenon of the antimony element in silicon and determining the supplementary doping time of the antimony element.

The invention relates to a preparation method of a silicon single crystal rod and a silicon wafer. Comprising a melting stage, a temperature adjusting stage, a welding stage, a seeding stage, a shouldering stage, an equal-diameter stage, an ending stage and a breaking stage which are carried out in sequence, in the equal-diameter stage, the pulling speed is controlled to be within a first pulling speed range, and the solid-liquid interface temperature gradient is controlled to be within a first gradient range; wherein the range of the first pulling speed ranges from 0.5 mm / min to 1.1 mm / min; the first gradient range is 3 DEG C / cm to 5 DEG C / cm. By reducing the temperature gradient of a solid-liquid interface and lowering the crystal pulling rate, the stability of a thermal field is enhanced, and sufficient conditions are provided for the composite reaction of Sii and V, so that the impurity capturing efficiency is improved, the internal purity of the crystal is improved, and the impurities are effectively removed.

The invention relates to the technical field of semiconductor material growth, and aims to solve the technical problems that the service life of a heating element is shortened due to single atmosphere sharing, the quality is difficult to guarantee due to many crystal defects, the single crystal production cost is high, and the production efficiency is low in the prior art. The invention discloses a single crystal growth device which is characterized by comprising a furnace body, a first chamber, a second chamber, a heating assembly, a growth assembly, an atmosphere isolation and heat conduction assembly, an atmosphere management system and a central control system, the atmosphere isolation and heat conduction assembly is used for separating the furnace body into a first cavity and a second cavity which are isolated in an airtight mode, and efficient heat transfer is achieved. By the adoption of the scheme, atmosphere structure separation and combined crucible design can be achieved, high quality and high purity of crystals are guaranteed, meanwhile, the service life of a heating element is effectively prolonged, and the operation cost is remarkably reduced.

The invention provides a method for controlling the resistivity drop amplitude of a heavily doped single crystal, and relates to the technical field of heavily doped crystal pulling, in the crystal pulling process, after the curing rate, through common adjustment of the pulling speed, pressure and argon, a crystal bar with the resistivity drop amplitude being less than or equal to 0.4 m omega when the resistivity is below low resistance is pulled; wherein the pulling speed is kept unchanged, the change amplitude of unit pressure is 5Kpa / 100mm to 30Kpa / 100mm, and the change amplitude of unit argon is 10slm / 100mm to 40slm / 100mm, as the current process cannot directly obtain that the head resistance is low resistance, after a certain curing rate, when the resistivity of a crystal bar reaches low resistance, the pulling speed, the pressure and the argon are jointly adjusted, so that the qualification rate is improved, and the production cost is reduced. Meanwhile, the stability is improved, and the standard deviation is reduced (N is equal to 10).

The invention provides a silicon single crystal rod and a preparation method thereof, a silicon wafer and a solar cell, the silicon single crystal rod contains hydrogen element, the silicon single crystal rod has a center and an edge along the radial direction of the silicon single crystal rod, and (CH1-CH2) / CH2 is more than or equal to 0 and less than or equal to 35%; and the dislocation density of the silicon single crystal rod meets the condition that (rho1-rho2) / rho1 is greater than or equal to-80% and less than or equal to 80%. According to the silicon single crystal rod provided by the invention, the hydrogen element is doped, and the distribution uniformity of the hydrogen element in the radial direction of the silicon single crystal rod is controlled, so that the recombination effect of defects such as dislocation and vacancy on carriers is effectively reduced in the radial range of the whole silicon single crystal rod, the minority carrier lifetime is prolonged, meanwhile, the stress distribution in the silicon single crystal rod is improved, and the service life of the silicon single crystal rod is prolonged. And the stress is more uniformly released on the cross section of the whole silicon single crystal rod, so that the mechanical property of the silicon rod is enhanced.

Provided is a GaAs wafer that can suitably be used to produce LiDAR sensors in particular and a method of producing a GaAs ingot that can be used to obtain such a GaAs wafer. The GaAs wafer has a silicon concentration of 5.0×1017 cm−3 or more and less than 3.5×1018 cm−3, an indium concentration of 3.0×1017 cm−3 or more and less than 3.0×1019 cm−3, and a boron concentration of 1.0×1018 cm−3 or more. The average dislocation density of the GaAs wafer is 1500 / cm2 or less.

The invention provides a silicon single crystal rod and a preparation method thereof, a silicon wafer and a solar cell. The invention provides a silicon single crystal rod. The silicon single crystal rod contains a hydrogen element. The ratio of the resistivity of the head of the monocrystalline silicon rod to the resistivity of the tail of the monocrystalline silicon rod is 0.8-2.0; and the dislocation density of the silicon single crystal rod meets the condition that (rho1-rho2) / rho1 is greater than or equal to-80% and less than or equal to 80%. The silicon single crystal rod provided by the invention is doped with the hydrogen element, so that the distribution uniformity of the doped element in the silicon single crystal rod is improved, the internal defects of the silicon single crystal rod in the growth process are reduced, and the overall mechanical property and electrical property of the silicon single crystal rod are improved by controlling the distribution of the dislocation density of the silicon single crystal rod within a reasonable interval.

The invention discloses a device and a method for inhibiting crucible oxidation and raw material decomposition in gallium oxide single crystal growth, the device comprises a furnace body, an iraurita crucible, a thermal insulation layer, an induction coil, a lifting mechanism and the like, a temperature dynamic regulation and control system is arranged between the iraurita crucible and the thermal insulation layer; the temperature dynamic regulation and control system is used for monitoring the temperature distribution of the iridium crucible and the inner cavity in real time and regulating the heating frequency of the induction coil through feedback temperature; a melt decomposition monitoring system is arranged in the inner cavity close to the iraurita crucible and is used for detecting the gallium atom concentration and oxygen partial pressure change in the inner cavity in real time; and an atmosphere active adjusting system is also arranged in the furnace body. According to the device, the gallium oxide single crystal can be obtained, and the problems of crucible oxidation, melt decomposition and unstable crystal quality caused by a high-temperature environment can be solved; through dynamic monitoring and regulation, the oxidation and corrosion loss of the iraurita crucible is reduced, and meanwhile, the large-size and high-quality beta-Ga2O3 single crystal is obtained.

The invention relates to the technical field of single crystal drawing, in particular to a single crystal drawing system. The single crystal drawing system comprises a single crystal furnace, a nitrogen supply unit and an argon supply unit, the single crystal furnace comprises a main chamber and an auxiliary chamber, the main chamber is communicated with the auxiliary chamber through a throat, the upper end of the auxiliary chamber is communicated with a first gas inlet main pipe which is communicated with the nitrogen / argon supply unit, and the throat is communicated with a second gas inlet main pipe which is communicated with the nitrogen / argon supply unit. Therefore, nitrogen can be used for replacing argon to serve as inert gas shielding gas in all stages or part of stages of single crystal drawing, so that the production cost is reduced; meanwhile, the thermal conductivity of nitrogen is higher than that of argon, so that heat can be transferred more effectively, a thermal field in the furnace is more uniform, the crystal growth stability is improved, and the generation probability of crystal defects is reduced. Meanwhile, at the crystal pulling temperature, nitrogen can inhibit volatilization of impurities in silicon to a certain extent, so that the impurities in the crystal are distributed more uniformly, and the electrical property of the crystal can be accurately controlled.

The invention discloses an edge-defined film-fed crystal growth method, which comprises: S1, placing a growth raw material in a crucible, placing a mold in the crucible, placing a seed crystal at a position 3-50 mm right above the mold through a seed crystal rod, the mold being provided with a curved surface inner cavity; s2, the upper heat preservation device and the middle heat preservation device are vacuumized and filled with inert gas; s3, performing exhaust treatment; s4, raising the temperature in the crucible to a first temperature, and melting the growth raw material in the crucible; s5, the seed crystal makes contact with the mold, the temperature is increased to a second temperature, and the seed crystal is pulled up; s6, reducing the diameter of the seed crystal, pulling the seed crystal for 5-10 mm, and cooling for the first time; s7, separating the crystal from the mold; and S8, annealing treatment is conducted after cooling. A uniform heating space is provided for growth of crystals, release of growth stress and thermal stress of the crystals is controlled, and impurities volatilized in the process of taking away the interior of the heat preservation device at high temperature are taken away through exhaust; the seed crystal is in contact with the curved-surface inner cavity of the mold to grow the curved-surface crystal, so that the cutting and rough machining cost is reduced.

The present disclosure provides a single crystal silicon, a method for manufacturing the same, and a silicon wafer, the method comprising: when applying a magnetic field to a raw material melt and pulling up the single crystal silicon by a Czochralski method, growing the single crystal silicon in such a manner that the magnetic field intensity is controlled to 2000-3000 gauss. The silicon single crystal thus grown has an oxygen concentration of 5.6 ppma or more and 8.5 ppma or less, an RRG in a crystal cross-section orthogonal to the growth direction of the silicon single crystal of 1% or less, a low oxygen concentration, and high uniformity of radial resistance distribution.

A single crystal metal wire preparation device comprises a furnace body with a containing cavity, and a smelting crucible provided with a heater is arranged in the containing cavity; the extension pipe is vertically connected to the lower side of the smelting crucible, the upper end of the extension pipe communicates with the interior of the smelting crucible, and an outlet is formed in the lower end of the extension pipe; the cooling pipe is wound on the lower part of the extension pipe, and the cooling pipe is used for introducing cooling liquid to cool the lower part of the extension pipe; and the traction material receiving mechanism is used for downwards dragging the metal wires growing out of the outlet of the extension pipe. According to the scheme, a large cooling gradient is formed between the upper portion and the lower portion of the extension pipe, after metal raw material molten liquid in the smelting crucible downwards flows into the extension pipe, the metal raw material molten liquid is cooled and grows into a single crystal metal wire, and the single crystal metal wire is pulled out of an outlet of the extension pipe under the action of the traction material collecting mechanism and then wound; and the cooling growth process of the single crystal metal wire is mainly carried out in the extension pipe, so that the single crystal metal wire is not easy to break, the production and processing stability is good, and the yield is high.

The present invention relates to a method for growing SiC crystals by a low-temperature solution method, and belongs to the technical field of crystal growth. After high-purity silicon, metal Fe or Cr, and rare earth metals are mixed and alloyed and smelted, the smelting time is 5-30min to obtain a Si-Me-RE alloy with uniform composition; the Si-Me-RE alloy is loaded into a high-purity dense graphite crucible or a SiC crucible in a crystal growth furnace, and the melting temperature is kept above 1823K for at least 1 hour, so that C or SiC is dissolved in the high-temperature melt to obtain a SiC-saturated Si-Me-RE-C melt; the SiC-saturated Si-Me-RE-C melt is subjected to solution method growth of SiC single crystals or polycrystalline SiC. The method for growing SiC crystals by a low-temperature solution method provided by the present invention solves the problem of low solubility of C or SiC when growing SiC crystals by a solution method, and can greatly increase the solubility of C or SiC in the Si melt at low temperature (at least 400K lower than the existing PVT method), and is a method for growing SiC crystals with low energy consumption, low cost, high efficiency, and no pollution.

The present application discloses a silicon carbide substrate with a stepped stress distribution, belonging to the field of silicon carbide production and processing technology. The silicon carbide substrate includes a first main surface and a second main surface; the first main surface has a first gradient stress interval, a second gradient stress interval surrounding the first gradient stress interval, and a third gradient stress interval surrounding the second gradient stress interval, the width of the third gradient stress interval extending inward from the edge of the substrate is 2.5-30mm, and the width of the second gradient stress interval extending inward from the edge of the third gradient stress interval is 10-50mm; the relative stress in the body of the first gradient stress interval is greater than or equal to the relative stress in the body of the second gradient stress interval, and less than the relative stress in the body of the third gradient stress interval. The relative stress in the body of each area of ​​the silicon carbide substrate is uniformly transitioned and is distributed in a stepped manner, which can improve the quality of the silicon carbide substrate and expand the scope of use of the silicon carbide substrate.

The utility model discloses a temperature gradient regulation and control device for large-size germanium single crystal growth, and belongs to the technical field of germanium crystal growth. The device comprises a furnace body, a guide cylinder, a heat preservation cylinder, a ventilation ring and a graphite crucible, the furnace body comprises a main chamber and an auxiliary chamber, and the auxiliary chamber is arranged at the top of the main chamber; the ventilation ring is a tubular metal circular ring, the circular ring is hollow, the inner diameter of the circular ring is larger than the equal diameter of growing germanium single crystals, a plurality of air outlets are evenly formed in the inner wall and the outer wall of the circular ring, an air inlet is formed in the top face of the circular ring, and the ventilation ring is installed on the upper portion of the inner side of the guide cylinder and tightly attached to the guide cylinder or installed on the upper portion of the outer side of the guide cylinder and tightly attached to the guide cylinder. Low-temperature protective gas is blown to the flow guide cylinder through the ventilation ring, so that the temperature of the flow guide cylinder is reduced, the low-temperature flow guide cylinder serves as a cold end, crystallization latent heat, especially crystallization latent heat in the shouldering stage, transmission of crystallization latent heat radiation during shouldering is accelerated, the shouldering probability of growing large-size germanium single crystals is increased, and the purpose that the large-size germanium single crystals enter the equal-diameter stage through shouldering is smoothly achieved.

The utility model discloses a single crystal furnace bottom heat preservation structure which is not easy to damage during disassembly and assembly, and comprises a furnace bottom heat preservation structure, an exhaust hole formed in the middle of the furnace bottom heat preservation structure and an electrode hole formed in the periphery of the exhaust hole, and a clamping groove device is arranged at the bottom of the furnace bottom heat preservation structure. The top of the clamping groove device is provided with a clamping groove used for a furnace bottom heat preservation structure to be inserted, and the side face of the clamping groove device is provided with a through groove communicated with the clamping groove. According to the single crystal furnace bottom heat preservation structure not prone to being damaged during disassembly and assembly, the furnace bottom heat preservation structure is conveniently inserted and embedded through the arranged clamping groove device and the arranged clamping groove, so that the furnace bottom heat preservation structure is protected and positioned, the furnace bottom heat preservation structure can be conveniently disassembled through cooperation with the arrangement of the through groove, and the furnace bottom heat preservation structure can be prevented from deviating; and the damage to the furnace bottom heat preservation structure caused by the tool during disassembly can be avoided.

A silicon carbide substrate having high crystal quality, belonging to the technical field of silicon carbide production and processing. The silicon carbide substrate comprises a first main surface and a second main surface; the first main surface has a central area and an annular area surrounding the central area, the width of the annular area extending inward from an edge of the substrate being 5-30 mm; the central area is divided into square areas, each having a side length of 5 mm, the internal stress of each square area being less than the internal stress of the annular area, and the internal stress being the stress value detected at least 30 μm vertically extending from the first main surface or the second main surface into the silicon carbide substrate. The internal stress in the central area of the silicon carbide substrate is relatively low.

The present disclosure provides a flow guide device, method and single crystal silicon growth furnace for single crystal silicon growth furnace, aiming at solving the problem of uneven crystal quality caused by the asymmetry of the circumferential thermal field in the furnace during the Czochralski single crystal silicon growth process. The device includes a fixedly arranged flow guide cylinder body, a plurality of independently adjustable asymmetric flow guide plates circumferentially arranged at the lower end or inner wall of the flow guide cylinder, a driving mechanism located outside the furnace, a sealed transmission assembly passing through the furnace wall, and a closed-loop control system containing sensors. Based on the real-time monitoring of the circumferential temperature distribution of the melt surface or the air flow pressure distribution, the control system independently adjusts the deflection angle of each flow guide plate through the driving mechanism, actively builds an asymmetric air flow field in the furnace, and dynamically compensates for the inherent or time-varying thermal field asymmetry of the furnace body. The present disclosure can significantly improve the thermal field uniformity of the crystal growth interface, reduce the density of primary particles and light scattering defects, and improve the uniformity of the radial oxygen content and resistivity of the crystal.

The invention discloses a high-temperature alloy turbine blade directional solidification method based on multistage dynamic gas protection control. The high-temperature alloy turbine blade directional solidification method comprises the following steps that a high-temperature alloy mother alloy material is put into a crucible; filling inert gas to a preset pressure, heating the crucible, heating to a preset temperature, and keeping the temperature to ensure that the alloy liquid is liquefied; continuously filling inert gas to preset pressure and then refining, wherein a vibration generator generates a magnetic field in the refining process to carry out electromagnetic vibration on the alloy liquid; continuously filling inert gas to preset pressure, and then transferring the crucible; inert gas is continuously filled to preset pressure, then the crucible is tilted, pouring is conducted, and in the pouring process, a gas purging device sprays the inert gas to conduct purging protection on the alloy liquid; and continuously filling inert gas to preset pressure, and pulling the shell to finish the directional solidification process. The method can reduce the gas content in the melt, prevent the melt from being oxidized, promote the removal of a surface oxidation film, reduce pores and oxidation film inclusion, and improve the purity, mechanical properties and yield of the casting.

The invention belongs to the technical field of semiconductor material processing, and particularly relates to a method for improving an OISF defect of an 8-inch light phosphorus-doped single crystal and a product thereof, and the method comprises the following steps: in the crystal pulling process, reducing the pulling speed, flattening a solid-liquid interface, balancing the growth rate and the release of thermal stress, so as to reduce the thermal stress and inhibit the formation of the OISF defect; the liquid opening distance is increased, the increase of the liquid opening distance enables the crystal to experience a slower cooling rate in the growth process so as to reduce the accumulation of thermal stress, so that the dislocation defect in the crystal is reduced, dislocation is a potential nucleation point of OISF, and therefore, the increase of the liquid opening distance can inhibit the formation of the OISF defect; after the crystal growth is finished, the cooling rate is increased, so that a crystal bar quickly passes through a temperature interval, the generation of O2V is reduced, the generation of OISF defects is avoided, oxygen atoms are in a solid solution state in the silicon crystal at high temperature, and the higher cooling rate can inhibit the diffusion and aggregation of oxygen, reduce the formation of oxygen precipitates, reduce the density of the OISF defects and also avoid the generation of the OISF defects; therefore, the OISF defect of the 8-inch light phosphorus-doped single crystal is reduced, and the electrical property of the 8-inch light phosphorus-doped single crystal is improved.

The utility model provides a protective disc tablet and a single crystal furnace, and relates to the technical field of single crystal silicon production. The protection disc pressing piece comprises a plurality of pressing piece split bodies which are circumferentially spliced. Target surfaces are arranged on the two circumferential sides of the tablet split body; the target surface is provided with a first concave part and a second concave part; the target surfaces of every two adjacent pressing piece split bodies are arranged in an attached mode, the first concave parts of every two adjacent pressing piece split bodies define a first stepped hole, the second concave parts of every two adjacent pressing piece split bodies define a second stepped hole, and the second stepped holes communicate with the first stepped holes; the cross sectional area of the first stepped hole is larger than that of the second stepped hole, and the second stepped hole is located in the side, close to the soft sticky piece, of the pressing piece split body. According to the protection disc pressing piece, the influence range of airflow can be limited in a relatively small area, and the situation that soft adhesive is blown up in a large area is avoided; meanwhile, the possibility that the soft adhesive is blown up under the action of airflow can be reduced, the cleanliness in the single crystal furnace is ensured, and the growth quality of single crystals is further improved.

The invention discloses a silicon single crystal rod and a preparation method thereof, a silicon wafer and a solar cell, and belongs to the technical field of photovoltaic module preparation. The single crystal silicon rod contains an antimony element and a hydrogen element, the doping concentration of the antimony element in the single crystal silicon rod is Ca, the doping concentration of the hydrogen element in the single crystal silicon rod is Cb, and Ca / Cb is greater than or equal to 1E <-3 > and less than or equal to 4E + 2. According to the silicon single crystal rod provided by the invention, the antimony and the hydrogen are doped at the same time, and the effective segregation coefficient of the antimony in the crystalline silicon is improved through the interaction of the hydrogen and the antimony, so that the resistivity change uniformity of the silicon single crystal rod is improved, the oxygen content of the silicon single crystal rod is improved, the service life of the silicon single crystal rod is prolonged, and the resistivity is accurately controlled; the resistivity of the monocrystalline silicon rod and the derivative product thereof is more uniform and concentrated, and the performance and the production efficiency of the czochralski monocrystalline silicon and the battery can be effectively improved.

The invention relates to a growth device and a growth method of silicon carbide crystals. The growth device comprises a crystal growth assembly, the crystal growth assembly comprises a raw material placement area, a gas guide structure area and a seed crystal placement area which are sequentially arranged from bottom to top; the air guide structure area comprises at least two layers of air guide units arranged in the vertical direction; the air guide units on the same layer comprise a plurality of air guide elements which are arranged in an array; each air guide element is of an integrated combined structure and comprises a first table body and a second table body. The first bottom face of the first table body and the first bottom face of the second table body are oppositely attached, and the top, away from the first table body, of the second table body is provided with a concave part. According to the growth device, the gas guide structure area is arranged in the growth device, and the structural design of the gas guide structure area is used for dredging the flowing direction and the flowing speed of component gas flow, and meanwhile, carbon particle impurities in raw materials are correspondingly blocked, so that the yield and the quality of silicon carbide crystals are improved.

The invention discloses a selenium gallium barium single crystal and a growth method thereof. The growth method of the selenium-gallium-barium single crystal comprises the following steps: placing a crucible containing BaGa4Se7 seed crystals and BaGa4Se7 polycrystals in a quartz tube, vacuumizing the quartz tube, filling argon into the quartz tube, and sealing the quartz tube in a melting manner; the quartz tube is placed in a crystal growth furnace, and the crystal growth furnace is vertically provided with a high-temperature area, a gradient cooling area and a low-temperature area from top to bottom in sequence; heating and melting the BaGa4Se7 polycrystal, and meanwhile, ensuring that at least part of the height of the BaGa4Se7 seed crystal in the vertical direction is not melted; cooling is conducted, the temperature of the melted materials is reduced, and crystal growth is conducted; and after the crystal growth is finished, reducing the temperature of the crystal growth furnace to room temperature, thereby obtaining the product. The selenium gallium barium single crystal which is large in size, few in crystal defect, good in integrity and uniform in structure can be prepared through the growth method.

The utility model relates to a single crystal furnace pipeline cleaning device which comprises an ash cleaning assembly, a pipeline cleaning assembly, a pipeline cleaning assembly and a pipeline cleaning assembly, and the ash cleaning assembly is mounted in an ash cleaning pipeline of a single crystal furnace; the ash removal pipeline comprises an ash removal main pipe and ash removal auxiliary pipes arranged on the two sides of the ash removal main pipe, and the ash removal auxiliary pipes intersect with the ash removal main pipe in a centering mode; the ash removal assembly comprises a driving part and an ash removal part stretching into the ash removal pipeline, and the ash removal part is vertically arranged in the ash removal pipeline and can stretch out and draw back in the pipeline. According to the single crystal furnace pipeline cleaning device, oxides deposited on the lower edge of the inner wall of the pipeline can be thoroughly cleaned, reverse ash can be reduced for vacuumizing and ash discharging operation after ash cleaning, the oxide dust is prevented from being attached in the furnace to the maximum extent, and the crystal pulling quality is improved.

The utility model relates to a single crystal thermal field heat insulation ring, which belongs to the technical field of photovoltaic manufacturing, is arranged on a heat preservation cylinder and comprises two symmetrically arranged semi-ring-shaped heat insulation ring bodies, a plurality of through holes are uniformly distributed on the heat insulation ring bodies along the semi-ring-shaped surfaces of the heat insulation ring bodies, the through holes penetrate through the heat insulation ring bodies, and the upper surfaces of the heat insulation ring bodies are obliquely arranged; the heat insulation ring is simple in structure, crystal pulling and oxygen reduction can be both achieved, the oxygen reduction effect is guaranteed, meanwhile, the unstable temperature gradient of a thermal field caused by installation of the heat insulation ring is improved, and the crystal pulling stability is guaranteed.

The present disclosure relates to the field of photovoltaic technology, and particularly relates to a method for drawing a single crystal silicon rod and a silicon wafer. The method comprises sequentially performed melting, seeding, shoulder-removing and constant-diameter processes. In the constant-diameter process, the following steps are implemented: setting a target furnace pressure and a preset upper limit value of a dry pump opening; adjusting the dry pump opening to control an actual furnace pressure in the furnace at the target furnace pressure; when the current opening of the dry pump is lower than the preset upper limit value, increasing the flow of protective gas into the single crystal furnace, and returning to perform the step of adjusting the dry pump opening based on the furnace pressure change until the opening of the dry pump is greater than or equal to the preset upper limit value. The present disclosure is at least beneficial to improving the electrical performance and yield of the single crystal silicon rod.

The present invention relates to a method for growing a gallium oxide single crystal and an apparatus for growing a single crystal, and according to one aspect of the present invention, the method includes providing a gallium oxide raw material in a crucible containing iridium, injecting carbon dioxide so that a preset carbon dioxide partial pressure is formed to suppress the loss of iridium, melting the gallium oxide raw material provided in the crucible, and producing a gallium oxide single crystal from the melt.

This invention discloses an argon gas protection system and crystal pulling method for reducing oxidation at the weld joint of seed crystals in a single crystal furnace. Multiple symmetrically distributed argon gas inlets are opened on the side wall of the throat connection section at the top of the main furnace chamber to form localized auxiliary argon gas. The auxiliary argon gas enters through the inclined inlets and is guided by a gas hood, causing the auxiliary argon gas discharged through the lower opening of the gas hood to flow downwards. A portion of the gas near the inner wall of the gas hood diffuses outwards to form an annular gas curtain surrounding the seed crystal, while a portion of the gas near the graphite chuck and the outer wall of the seed crystal is guided downwards along the wall to the weld joint for localized cooling, reducing oxidation at the weld joint and preventing iridescence, thus extending the number of uses.