217results about "Under a protective fluid" patented technology

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.

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 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 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 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.

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.

The utility model relates to the technical field of monocrystalline silicon production, and discloses gas recycling equipment which comprises a production device, the device is used for producing monocrystalline silicon; a gas inlet channel of the recycling mechanism is communicated with the gas outlet end of the production device, and a gas outlet channel of the recycling mechanism is communicated with the gas inlet end of the production device, so that a gas recycling loop can be formed; and the supplementing mechanism communicates with the gas inlet end of the production device so that gas can be conveyed to the production device. The gas recycling equipment can ensure that the pressure in a production device is stable, the production stability of the production device is improved, the production efficiency is improved, the product quality is improved, and the cost required by gas recycling is reduced.

Ingot puller apparatus and methods for growing single crystal silicon ingots with reduced lower chamber deposits are disclosed.

The invention discloses an intelligent crystal growth regulation and control system based on real-time oxygen and carbon detection, and particularly relates to the technical field of crystal growth regulation and control. The system comprises an oxygen-carbon and growth state signal acquisition module, a crystal growth stage judgment module, an oxygen-carbon detection signal calibration module, a crystal growth environment regulation scheme generation module and a growth environment regulation and control execution module, wherein the crystal growth stage judgment module further comprises a signal reference extraction sub-module and a difference comparison and adjustment sub-module; according to the invention, oxygen-carbon signals and growth state related signals are synchronously collected, growth stages are discriminated in combination with growth duration and heating power, oxygen-carbon detection signals are calibrated by adopting corresponding standards for different stages, the change rate is calculated according to the calibrated signals, and an environment adjustment scheme is generated by matching an adjustment proportion, so that the growth environment is accurately regulated and controlled; the accuracy of detection signals is improved, the stability of crystal growth parameters is guaranteed, the crystal growth quality is optimized, and the regulation adaptability and pertinence are enhanced.

The utility model relates to the field of monocrystalline silicon, in particular to a monocrystalline silicon interstitial oxygen eliminating system which comprises a single crystal furnace, a crucible and a graphite supporting component are arranged in the single crystal furnace, and the graphite supporting component comprises a graphite pot and a graphite supporting rod. The graphite supporting part further comprises an air supply channel, the air supply channel is provided with an air outlet and an air inlet, the air outlet is formed in the bottom face of an inner cavity of the graphite pot, and the air inlet is formed in the lower end of the graphite supporting rod. An air outlet is formed in the bottom surface of the inner cavity of the graphite pot; a hollow structure is arranged in the bottom structure layer of the graphite pot, the hollow structure is communicated with air outlets formed in the bottom of the inner side of the graphite pot, and the air inlets are communicated with the hollow structure; the gas supply system comprises an argon tank and a gas heating device; the air supply port is communicated with a cold air inlet of the air heating device, and a hot air outlet of the air heating device is communicated with the air inlet; when air enters the bottom of the crucible from the air outlet, hot air is distributed more uniformly, interstitial oxygen in monocrystalline silicon is distributed better, and the removal efficiency is higher.

The utility model discloses a silicon solar energy industry nitrogen residual cold recovery device which comprises a vortex tube, a first three-way valve, a second three-way valve and a heat exchange mechanism, the input end of the vortex tube is communicated with a nitrogen exhaust port of a condensation evaporator in a photovoltaic workshop, and the hot air output end of the vortex tube is communicated with the input end of the first three-way valve. The cold air output end of the vortex tube communicates with the input end of the second three-way valve; the first output end of the first three-way valve and the first output end of the second three-way valve are both connected with gas discharge ends, and the second output end of the first three-way valve and the second output end of the second three-way valve are both communicated with the heat exchange mechanism. Nitrogen in a silicon solar crystal pulling and slicing manufacturing section is collected in a centralized mode and sequentially passes through the vortex tube and the heat exchange mechanism, energy recovery is achieved, the problem that in the prior art, resources are wasted due to direct nitrogen discharging is solved, and recycling of the resources is facilitated.

The utility model provides a water cooling screen for a monocrystalline silicon growth device, and belongs to the field of monocrystalline silicon material production equipment. The water cooling screen comprises a liquid inlet, a liquid outlet, an inner wall, an outer wall and an annular flow channel. The liquid inlet and the liquid outlet are respectively formed in the upper end of the water cooling screen, the liquid inlet is communicated with the bottommost layer of the annular flow channel, and the liquid outlet is communicated with the uppermost layer of the annular flow channel; the outer wall is of a thin-wall hollow structure, the hollow structure comprises an inner layer and an outer layer, and the outer layer and the inner layer are sealed at the end part to form an air interlayer; and the outer layer exposed side is a polishing layer / reflective layer. Meanwhile, the bottom face of the annular flow channel can be of the same hollow structure. According to the utility model, the absorption of heat on the outer side of the water-cooling screen is reduced, so that the heat loss of the silicon melt is weakened, the energy consumption is reduced, the production cost is reduced, and the production efficiency is improved.

The invention relates to the field of semiconductor materials, in particular to a crystal pulling thermal field control method, a crystal pulling thermal field system and application. The crystal pulling thermal field control method comprises the following steps: in an equal-diameter growth stage of czochralski silicon, when the curing rate of a silicon rod is less than or equal to 30%, controlling the argon flow to be 90-120SLPM, and controlling the furnace pressure to be 800-1000Pa. According to the crystal pulling thermal field control method, in the initial stage of equal-diameter growth where the oxygen segregation effect is most sensitive, argon flow and furnace pressure are cooperatively controlled in a specific'low flow-low pressure 'window, and a process environment beneficial to oxygen volatilization instead of entering crystals is actively created. The segregation and doping of oxygen atoms to a solid-liquid interface are effectively inhibited from the aspect of dynamics, and the method is the most critical step for realizing the overall low oxygen content of the silicon rod, especially reducing the oxygen content of the head and improving the axial uniformity.

An apparatus for process-safe production of single crystals includes a process chamber that is fillable with a process gas and that receives a heatable growth cell, a heating device for heating the growth cell, which is adapted to receive a source material and a seed, and a vessel at least radially enclosing the process chamber and comprising at least first and second segments. A related method is also disclosed.

Disclosed herein is an apparatus for producing a single crystal, the apparatus comprising: a furnace wherein the furnace comprises a furnace wall, a furnace substrate, and a furnace lid; the furnace wall is arranged between the furnace base plate and the furnace cover; the growth chamber comprises an outer pipe, a growth chamber bottom plate and a growth chamber top plate; wherein the furnace lid has an opening through which the growth chamber protrudes, and wherein the growth chamber operates to contain a crucible containing a melt for producing a single crystal; a pull rod contacting the melt to produce an ingot; and a conduit disposed between the furnace wall and the outer tube of the growth chamber; wherein the conduit is operative to transport an inert gas through the furnace to heat the inert gas and deposit the heated inert gas into the growth chamber.

The invention relates to the technical field of photovoltaics, in particular to a single crystal furnace, a preparation method of a single crystal silicon rod and a silicon wafer. The single crystal furnace comprises a guide cylinder and a crucible, wherein the guide cylinder is positioned on the top side of the crucible; the adjusting mechanism is provided with a first adjusting part and a second adjusting part, one end of the first adjusting part is rotatably connected to the outer side wall of the bottom of the guide cylinder, and the other end of the first adjusting part is rotatably connected to the second adjusting part; the second adjusting part can move in the preset direction, and the preset direction is parallel to the direction from the top side of the guide cylinder to the bottom side of the guide cylinder. By controlling the second adjusting piece to move, the first adjusting piece can be driven to rotate, so that the form of a gas channel between the guide cylinder and the crucible is adjusted, the gas flow distribution in the furnace is optimized, the quality of a prepared monocrystalline silicon rod is improved, and the resistivity measurement accuracy is further improved.

The invention discloses a system and a method for directly and continuously preparing a silicon single crystal rod from polycrystalline silicon, and belongs to the technical field of preparation of semiconductors and photovoltaic materials. The system comprises a reduction furnace, a liquid silicon conveying unit and a single crystal furnace which are sequentially communicated, and atmosphere isolation is guaranteed through pressure control. The method comprises the following steps: carrying out chemical vapor deposition on polycrystalline silicon in a reduction furnace by using a high-temperature-resistant metal electrode; then raising the temperature to melt the polycrystalline silicon into a liquid state in situ and collecting; and the liquid silicon is directly conveyed into the single crystal furnace through the heat tracing pipeline to carry out Czochralski single crystal growth. According to the invention, a plurality of independent discrete procedures of polycrystalline silicon preparation, crushing treatment, secondary melting and single crystal drawing in the traditional process are innovatively integrated in a closed and continuous system, so that all intermediate physical circulation links are omitted, the introduction of impurities is fundamentally avoided, the energy consumption and the production cost are remarkably reduced, the production period is greatly shortened, and the production efficiency is improved. The product purity and the production efficiency are improved.

The application belongs to the technical field of inorganic functional crystals, and particularly relates to a praseodymium ion doped phosphate crystal material and a preparation method and application thereof. The application provides a praseodymium ion doped phosphate crystal material, a chemical formula of the praseodymium ion doped phosphate crystal material is shown as formula 1: Ba3Y 1‑x (PO4)3:xPr formula 1; in formula 1, 0

This application relates to the field of single crystal furnace technology, providing a single crystal furnace and a crystal pulling method. The single crystal furnace includes a main chamber and a water-cooled screen. The water-cooled screen is located in the main chamber and includes a screen body, a first cooling structure, and a second cooling structure. The screen body forms an intermediate channel for single crystal growth. The first cooling structure is located on the screen body, and the second cooling structure is located above the first cooling structure and at least partially connected to it. The second cooling structure includes a first venting element and a second venting element arranged opposite to each other, spaced apart circumferentially along the intermediate channel. The first venting element sprays a first doping gas and a protective gas, and the second venting element sprays a second doping gas and a protective gas. The single crystal furnace provided by this application at least helps to solve the technical problem in related technologies where it is difficult to accurately control the concentration and uniformity of the axial resistivity of single crystal silicon.

The application relates to the field of semiconductor growth, in particular to a pulling shaft of a single crystal furnace, which is applied to the single crystal furnace and comprises a hard shaft, the hard shaft is in a long straight state and is vertically arranged; a soft shaft, the first end of the soft shaft is connected to the bottom of the hard shaft, and the soft shaft is coaxially arranged with the hard shaft; and a clamp assembly, the clamp assembly is connected to the second end of the soft shaft, and the clamp assembly is used for clamping a seed crystal. The technical problem that the crystal pulling quality is not high is solved, and the technical effect that the crystal quality is improved is achieved.