1454results about "By pulling from melt" patented technology

The invention relates to a czochralski method-based crystal growth interface shape detection method and device. The method comprises the steps that: a seed crystal temperature T and an interface electromotive force U at the same time in a crystal growth process are collected, and a T-U curve of the interface electromotive force U changing with the seed crystal temperature T is obtained; the change trend of the shape of a crystal growth interface in real time is judged by observing the deviation between the T-U curve and a reference line, wherein the reference line is a straight line passing through the starting point of the T-U curve, and the slope of the straight line is the Seebeck coefficient of the crystal. The invention also relates to a device used by the method. The detection method provided by the invention can detect the change trend of the shape of the crystal growth interface in real time in the crystal growth process, and can be applied to Czochralski method growth equipment for various single crystals such as lithium niobate, lithium tantalate, sapphire, yttrium aluminum garnet and the like.

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 provides a crystal growth device and a crystal growth method for separating crystals from melts, and solves the defect that polycrystals are easy to generate during crystal growth at present. The growth device comprises a heat preservation furnace, a heater, a crystal growth crucible, a lining crucible, a lifting mechanism, a ceramic lifting seat, pressing graphite, a heat conduction graphite ring and a heat preservation ring, the crystal growth crucible is coaxially arranged in the heat preservation furnace; the heater is coaxially arranged between the crystal growth crucible and the holding furnace; the lining crucible is coaxially arranged in the crystal growth crucible and comprises a crucible bottom plate, a melt transmission channel and a crucible main body which are coaxial and communicated from bottom to top; in order to reduce the influence of the melt on the crystal in the growth process, the crystal and the melt are physically separated, the growth device with the two crucibles is designed, and in consideration of the importance of stable crystal growth thermal field environment, heat transfer of the two crucibles is isolated through the heat preservation ring; the heat-conducting graphite is used for uniformizing the temperature of the center and the edge of the melt, and concave liquid surfaces are avoided.

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 relates to the technical field of crystal growth, in particular to a device and a method for diversion growth of silicon carbide single crystals. The invention provides a device for diversion growth of silicon carbide single crystals. The device comprises a crucible, a first rotary lifting shaft and a turbine liquid pump kit, the turbine liquid pump kit comprises a flow guide baffle, the upper portion of the flow guide baffle is connected with the first rotary lifting shaft, a seed crystal support with seed crystals is installed on the lower portion of the flow guide baffle, turbine blades are installed on the flow guide baffle and evenly distributed around the seed crystals, and the height of the lower ends of the turbine blades is smaller than that of the seed crystals. The invention provides a device and a method for diversion growth of silicon carbide single crystals, which can improve the transmission stability and transmission efficiency of solute in a solution and improve the long-time growth stability of crystals.

The invention provides a single crystal furnace crystal pulling ending parameter control method and system based on adaptive regulation, and the method comprises the steps: collecting production data and parameter data of an ending starting point through a distributed sensor network and a processing equipment interface, and processing the data to obtain current state data of a crystal; and performing similarity comparison on the current state data of the crystal to obtain initial process parameters of the ending stage, and deducing and predicting state expectation evolution data of the crystal in the ending process based on the current state data of the crystal and the initial process parameters. According to the method, through the synergistic effect of full-state perception, foresight deduction, risk quantification and self-adaptive regulation and control, the bubble capture risk index is stably controlled to be 0.5 or below, the stability of a solid-liquid interface in the ending stage is improved, the technological process is not affected by the experience level of operators, and the optical uniformity consistency between batches is greatly improved.

The invention provides a crystal pulling method for improving the BMD defect density in monocrystalline silicon and a monocrystalline silicon rod, and belongs to the technical field of monocrystalline silicon crystal pulling, and particularly relates to the following steps: stabilizing the oxygen content in a crystal in a relatively high interval by cooperatively regulating and controlling the argon flow, the furnace pressure, the crucible rotating speed, the crystal rod rotating speed and the pulling speed, providing a sufficient oxygen source for generation of BMD defects, and improving the BMD defect density in the monocrystalline silicon on the basis of stabilizing the oxygen content in the crystal in a relatively high interval. In the equal-diameter process, temperature compensation is carried out on a crystal bar through a preset temperature compensation device, diffusion and precipitation of oxygen atoms are effectively promoted to form BMD crystal nucleuses, the BMD body defect density and the axial distribution uniformity are remarkably improved, the specification lower limit of the BMD density is promoted to be improved to 1.0 E + 11 ea / cm < 3 > or above, the internal gettering capacity of a silicon wafer is finally enhanced, and the service life of the silicon wafer is prolonged. And a reliable guarantee is provided for improving the performance and yield of the device.

A crystal pulling method and system for fabricating a large-diameter silicon single crystal, and a silicon single crystal and a medium. The method can comprise: performing global two-dimensional simulation on a crystal pulling process, and acquiring a global temperature distribution, a velocity field distribution and an initial solid-liquid interface value during the crystal pulling process under a preset crystal pulling apparatus and a preset crystal pulling parameter; on the basis of the global temperature distribution and the velocity field distribution, determining a boundary condition, and on the basis of the boundary condition, performing local three-dimensional simulation on the crystal pulling process to determine a target solid-liquid interface value; adjusting the preset crystal pulling parameter until the initial solid-liquid interface value is equal to the target solid-liquid interface value within a threshold range, and using the adjusted preset crystal pulling parameter as a reference crystal pulling parameter; on the basis of the reference crystal pulling parameter, simulating and calculating a simulated defect during the crystal pulling process; on the basis of the simulated defect, iteratively optimizing the reference crystal pulling parameter until the simulated defect meets a preset condition, and using the optimized reference crystal pulling parameter as a target crystal pulling parameter; and fabricating a defect-free silicon single crystal.

A device for crystal growth and a crystal growth method. The device comprises a seed crystal holder, a seed crystal connecting rod, and a state detection assembly. The seed crystal holder is connected to one end of the seed crystal connecting rod, and the state detection assembly is configured to detect a seed crystal holder state of the seed crystal holder, wherein the seed crystal holder state reflects the state of the seed crystal holder relative to a melt, and the melt is used for crystal growth.

The invention provides a crystal pulling method for improving light boron-doped crystal BMD and a silicon single crystal rod, and belongs to the technical field of silicon single crystal pulling, crystal rod pulling is carried out in a predetermined thermal field to change the temperature gradient in the thermal field and increase the interval length of the BMD nucleation temperature, and in the crystal pulling process, the BMD nucleation temperature is increased. According to the present invention, the crystal rotation, the crucible rotation and the pulling speed are adjusted so as to improve the concentration and the distribution uniformity of the interstitial oxygen and the vacancy in the crystal bar, such that the concentration and the distribution uniformity of the interstitial oxygen and the vacancy in the crystal bar are pre-improved so as to provide sufficient raw materials for BMD nucleation, and then the temperature gradient in the thermal field is changed so as to increase the interval length of the BMD nucleation temperature, interstitial oxygen and vacancies are promoted to generate BMD, and then the BMD defect density in the light boron-doped crystal is remarkably improved through the synergistic effect of a preset thermal field, crystal transition, crucible transition and the pulling speed.

The invention provides a quartz crucible crushing device and method.The quartz crucible crushing device comprises a vibration platform, a clamping assembly and a knocking assembly, the vibration platform is used for placing a carbon-carbon crucible with a quartz crucible, the outer side wall of the carbon-carbon crucible is placed on the vibration platform, and the clamping assembly is used for clamping the carbon-carbon crucible; the clamping assemblies are oppositely arranged on the two sides of the vibration platform and used for clamping the carbon-carbon crucible, and the knocking assembly is arranged on the side, not provided with the clamping assemblies, of the vibration platform, can move along the inner side wall of the quartz crucible and is used for knocking the inner side wall of the quartz crucible. The automatic crushing device has the beneficial effects that automatic crushing of the quartz crucible is achieved in a knocking and vibrating mode, the crushing effect is guaranteed, the working intensity is reduced, potential safety hazards are reduced, the working efficiency is improved, damage to the carbon-carbon crucible is reduced, and the service life of the carbon-carbon crucible is prolonged.

The present application relates to a kind of methods and applications of growing bismuth-doped rare-earth iron garnet BRIG crystal by guided mode pulling-top seed crystal method.For solving the problems of large internal stress, many defects, difficult to prepare thick film of single crystal in the current liquid phase epitaxy method of growing BRIG crystal;And the problems of long growth cycle, difficult to obtain seed crystal in top seed crystal method, the present application combines the fast growth of guided mode pulling crystal and the high-quality single crystal growth of top seed crystal method, and invents guided mode pulling-top seed crystal method to realize the fast growth of high-quality BRIG single crystal.First, the large-size doped rare-earth iron garnet crystal with high lattice matching and similar composition is quickly grown by guided mode pulling method, which is cut into centimeter-level seed crystal, and high-quality BRIG bulk single crystal is quickly grown by TSSG method.The crystal grown by this method has the advantages of small internal stress, less cracking, good uniformity, fast crystal growth, etc., and has obvious advantages in high-performance magneto-optical isolator.

The invention relates to a silicon single crystal drawing method capable of reducing the resistivity range of a whole silicon single crystal rod, which belongs to the technical field of wafer processing and comprises the following operation steps of: 1, completely melting a solid silicon material and a doping agent into liquid in a crucible a; and 2, slowly lowering the crucible position in the crucible b to realize that a part of liquid at the bottom of the crucible is slowly solidified into a solid from the bottommost part. And 3, after the crucible in the crucible c is slowly lowered and stopped, seeding, shouldering and equal-diameter operation are carried out. And 4, carrying out an equal-diameter growth stage in the d crucible. And 5, continuously growing the single crystal rod in the e crucible. And 6, finishing silicon single crystal drawing in the crucible f through an ending process. An initial state of'high-concentration melt + low-concentration solid 'is constructed before crystal pulling, and real-time and dynamic dilution compensation is performed on the concentration of a dopant of a main melt, so that the inherent defect of resistivity axial non-uniformity caused by a segregation effect in a traditional Czochralski method is effectively overcome.

The invention belongs to the technical field of semiconductor crystal growth, and particularly relates to a magnetic field dynamic adaptation system and method for improving single crystal oxygen content uniformity, the melt liquid level height H is sensed in real time through a liquid level position sensing unit, thermal field state data W is obtained through a temperature zone monitoring unit, and the single crystal oxygen content uniformity is improved on the basis of the melt liquid level height H and the thermal field state data W. And the control module converts the target position Pz into a driving instruction and sends the driving instruction to the magnetic field execution module to drive the magnetic field execution module to synchronously and dynamically adjust the magnetic field space position of the magnetic field generator, converts the target intensity Btarget into a driving instruction and sends the driving instruction to the magnetic field execution module to drive the magnetic field execution module to synchronously and dynamically adjust the magnetic field intensity of the magnetic field generator. The magnetic field space position of the magnetic field generator is dynamically adjusted to promote oxygen to be conveyed uniformly, so that the radial oxygen concentration CV value is reduced, the magnetic field intensity of the magnetic field generator is dynamically adjusted to avoid nonlinear fluctuation in the oxygen segregation process, and the linearity of an axial oxygen distribution curve is improved.

The invention provides a semiconductor silicon single crystal growth value prediction method based on event trigger learning, and belongs to the technical field of silicon single crystal growth prediction. Comprising the following steps: constructing a value state space model according to a silicon single crystal growth mechanism; embedding the value state space model into a long short-term memory network to construct a network model; an attention mechanism is introduced into the network model, weighted fusion processing and physical constraint mapping processing are carried out in sequence, and the network model is constructed; based on an event triggering learning mechanism, training and adjusting the network model by utilizing historical time sequence data of the semiconductor silicon single crystal growth value to obtain a trained network model; and inputting the technological parameters at the current moment into the trained network model, and predicting the growth value of the semiconductor silicon single crystal at the next moment. According to the method, the accuracy, the real-time performance and the self-adaptive updating capability of semiconductor silicon single crystal growth value prediction can be improved.

The invention provides a single crystal silicon rod drawing method and system based on dynamic parameter linkage, and the method comprises the steps: implementing a temperature gradient dynamic control strategy according to different stages of single crystal silicon rod drawing; a linkage strategy of a rotation rate and a pulling speed is adopted, and the rotation rate of the seed crystal is kept at a high rotation speed in the initial stage of pulling to stabilize a melt interface; meanwhile, a stepped dynamic adjustment strategy is adopted for the lifting speed, low-speed lifting is kept in the initial stage so as to ensure the melt stability, and then the lifting speed is linearly increased according to the increase of the diameter of the silicon rod; and the crucible lifting speed is adjusted in real time based on a self-adaptive adjustment strategy, so that the crucible lifting speed and the increase of the diameter of the silicon rod are kept synchronous, the stability of the melt liquid level height is maintained, and the fluctuation of the dopant concentration is prevented. By dynamically adjusting the temperature gradient, the rotation rate, the pulling speed and the crucible lifting speed, thermal stress is reduced, melt convection is stabilized, the radial uniformity of the silicon wafer is improved, and the requirements of a BC battery for low-defect and high-uniformity doping are met.

The invention discloses a crystal growth method for avoiding formation of a gallium oxide polycrystal shoulder, and belongs to the technical field of crystal growth. The length of the slit on the surface of the mold is designed to be not more than one third of the length of the mold, and melt supply is strictly limited in a local area of the slit in a seeding stage, so that accurate starting of single crystals is realized; and then, in a crystal lateral expansion stage, actively regulating and controlling the interval between the upper surface of the mold and a crystal growth interface, so that a melt layer in the interval is used as a dynamic and expandable raw material supply channel. Therefore, the technical prejudice that a traditional edge-defined film-fed method depends on full-length solid slit feeding penetrating through a mold is broken through, a melt exposure area is reduced to be near a growth interface, spontaneous nucleation of a melt in a non-target area is fundamentally inhibited, formation of a polycrystal shoulder (square shoulder) is effectively avoided, raw material volatilization is remarkably reduced, thermal field uniformity is improved, and the method is suitable for large-scale production. And the crystal quality, the growth stability and the process efficiency are improved.

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 provides a preparation method for improving resistivity uniformity of a whole rod of heavily-doped monocrystalline silicon, and relates to the technical field of heavily-doped monocrystalline silicon drawing, in the crystal drawing process, crystal bar drawing is carried out through first furnace pressure from seeding to growing to a first equal-diameter preset length; drawing a second equal-diameter predetermined length from the first equal-diameter predetermined length, and reducing the furnace pressure according to a predetermined rate to reduce the first furnace pressure to a second furnace pressure; after the diameter is equal to a second preset length, crystal bar drawing is carried out through second furnace pressure; in the crystal growth process, along with crystal growth and furnace pressure stage reduction, segregated doped gas is continuously volatilized, so that the resistivity of the tail of a crystal bar is improved, the axial resistivity fluctuation range is controlled within + / -5%, and the harsh requirement of a high-end semiconductor device for a substrate material is met.

The invention belongs to the technical field of chemical metallurgy, and particularly relates to a device for stably growing silicon carbide single crystals by a liquid phase method and a working method.The device for stably growing the silicon carbide single crystals by the liquid phase method comprises an inner crucible, an outer crucible, a plurality of liquid discharging holes, a plurality of liquid discharging holes, a plurality of liquid discharging holes and a plurality of liquid discharging holes, the outer crucible is arranged on the periphery of the inner crucible in a sleeving mode, and an annular guide block used for stretching into the annular cavity and blocking the liquid drainage hole sets is arranged at the cavity bottom of the outer crucible; the driving shaft is connected with the outer crucible; the heater is positioned on the periphery of the outer crucible; the control module is electrically connected with the driving shaft; according to the device for stably growing the silicon carbide single crystals through the liquid phase method and the working method, the driving shaft rotates forwards to drive the outer crucible to descend, so that the annular guide block opens the liquid discharge hole group, and at the moment, the liquid level of a solution in the inner crucible is lowered to be away from a floating crystal.

The invention belongs to the technical field of high-temperature-resistant containers, and provides a quartz crucible preparation method and a quartz crucible. The preparation method of the quartz crucible comprises the following steps: preparing the matrix; the base body is subjected to heating pretreatment; coating the inner wall of the substrate with a barium solution; sintering to form a barium silicate prefabricated layer on the inner wall of the substrate; and barium carbonate powder is scattered on the barium silicate prefabricated layer to form a barium silicate protective layer. According to the quartz crucible prepared by the quartz crucible preparation method provided by the invention, the barium silicate protective layer in the quartz crucible can effectively prevent a product to be prepared from corroding the quartz crucible.

The invention discloses an edge-defined film-fed back crystal growth real-time regulation and control method, which relates to the technical field of crystal growth control, and comprises the following steps: obtaining time sequence data of process parameters, and constructing a real-time process path; the path similarity is obtained by calculating the cosine similarity average value of the real-time path and the standard path; based on whether the similarity exceeds a threshold value or not, the system adopts different regulation and control strategies: if yes, fine adjustment based on single-parameter instantaneous deviation is carried out; if not, starting path correction; according to path correction, a main deviation dimension is recognized, a weighting matrix is constructed, a weighting difference value of a current state and a target track is input into a technological process inverse model, an adjustment instruction sequence is calculated, and a first instruction is executed immediately; the control strategy can be intelligently switched according to the deviation degree, and the problem that system oscillation is aggravated due to the fact that coupling between parameters is ignored in traditional single-parameter control is avoided.

The invention discloses an indium phosphide single crystal growth dynamic thermal field control method based on AI calibration of multiple temperature zones, and relates to the technical field of semiconductor material preparation and artificial intelligence control. According to the method, a multi-temperature-zone thermal field digital twin model is constructed, multi-channel temperature data, heating power data and crystal growth image data in an indium phosphide single crystal growth furnace are collected, and real-time three-dimensional reconstruction of thermal field distribution in the furnace is carried out; with the crystal growth rate, the solid-liquid interface shape and the thermal stress distribution as optimization targets, power adjustment instructions of heaters in all temperature zones are output; an AI calibration module is introduced to correct thermophysical parameters of the digital twin model; deducing a thermal field state at a future moment, compensating a thermal hysteresis effect in advance, and realizing accurate closed-loop control of an indium phosphide single crystal growth process; according to the invention, the problem that the traditional PID control is difficult to cope with nonlinear, strong-coupling and large-lag thermal field change in large-size crystal growth is solved, and the single crystal yield and the lattice quality are remarkably improved.

This application relates to a silicon wafer, where a concentration of an antimony element in the silicon wafer ranges from 4E+14 cm-3 to 2E+16 cm-3, preferably ranges from 4.30E+14 cm-3 to 1.9E+16 cm-3, and further preferably ranges from 4.45E+14 cm-3 to 1.87E+16 cm-3; and a minority carrier lifetime of the silicon wafer is greater than or equal to 200 µs, preferably greater than or equal to 300 µs, and further preferably greater than or equal to 500 µs. This application further relates to another silicon wafer, where a concentration of an antimony element in the silicon wafer ranges from 4E+14 cm-3 to 2E+16 cm-3, preferably ranges from 4.30E+14 cm-3 to 1.9E+16 cm-3, and further preferably ranges from 4.45E+14 cm-3 to 1.87E+16 cm-3; and a minority carrier lifetime of the silicon wafer is greater than or equal to 300 µs, preferably greater than or equal to 400 µs, and further preferably greater than or equal to 600 µs.

The invention relates to the technical field of semiconductor material preparation, in particular to a quartz crucible and a preparation method thereof, and a preparation method of a large-size N-type silicon rod. The quartz crucible comprises a quartz crucible body and a doping material dispersed in the quartz crucible body. According to the quartz crucible, the doping material is directly and uniformly dispersed in the base material of the quartz crucible body, so that the doping agent is continuously, controllably and uniformly released in the high-temperature silicon melting process.

Apparatuses and methods as described herein can be used to grow a Ga2O3 based single crystal using an Edge-defined film fed growth (EFG) method. The single gallium oxide crystal sheet can have a principle plane is offcut from a (100) crystallographic orientation. In one embodiment, the offcut is between 2 and 20 degrees. The single crystal can have a full width half mass of less than 50arcsec.

According to the invention, heavy arsenic doping 1t is reduced; 111gt, 111gt; the invention relates to a crystal pulling method based on crystal orientation monocrystalline silicon section defect density and a monocrystalline silicon rod, and belongs to the technical field of monocrystalline silicon pulling. In the equal-diameter process, the liquid opening distance is constant, the pulling speed of the crystal bar is gradually reduced according to the length of the crystal bar, and the ratio (CR / SR) of crystal rotation / pot rotation is adjusted, so that heat conduction is uniformly transmitted in the radial direction of the crystal bar by controlling the growth rate of crystals, the temperature gradient of a solid-liquid interface and precipitation of oxides, and the heat conduction efficiency is improved. And in the crystal growth process, point defects such as interstitial atoms and vacancies have more opportunities to diffuse outwards, so that the generation of the point defects and impurity decorations is inhibited, the defect density of the section of the single crystal silicon rod is reduced, and the quality of the heavily arsenic-doped crystal rod is improved.

Apparatuses and methods as described herein can be used to grow a β-Ga2O3 based single crystal using an Edge-defined film fed growth (EFG) method. The method can include bringing a seed crystal in contact with a Ga2O3 base melt, pulling the seed crystal to grow the β-Ga2O3 based single crystal, wherein the β-Ga2O3 based single crystal has a (010) crystallographic orientation as it is being grown, and cooling the β-Ga2O3 based single crystal after it has reached a length that is greater than 40mm. In one embodiment, the method includes growing the scintillation crystal without defects.

The invention discloses a method, a device, equipment and a medium for controlling a Czochralski process, and belongs to the field of Czochralski. Observation variables in the single crystal straight pulling process are obtained and comprise the bright ring outer ring radius, the melt mass and the liquid opening distance. Then, based on a state space model, according to the observation variables, the internal state of the single crystal straight pulling process is estimated, and estimation variables including the estimated crystal radius and the estimated meniscus height are obtained; and then taking the estimated variable as an initial state, determining a predicted change track of an internal state based on a state space model, and generating and executing a control instruction based on the predicted change track by taking a target crystal radius and a target meniscus height as control targets. According to the scheme, through multi-variable collaborative estimation and predictive optimization, the problems that variables are strongly coupled, the internal state cannot be directly measured, control lags and the like in the czochralski single crystal growth process are solved, technical support is provided for preparing high-quality large-size single crystal silicon, and the crystal diameter control precision is improved.

The invention provides a method for reducing OSF of large-size Czochralski monocrystalline silicon, and relates to the technical field of large-size Czochralski monocrystalline silicon. In the crystal pulling process, the rotating speed of a crucible and the reduction amplitude of heating power are reduced in the later stage of shouldering, so that a set vacancy type point defect area is formed in advance, and the OSF of the large-size Czochralski monocrystalline silicon is reduced; increasing the rotating speed of the crucible and increasing the reduction amplitude of heating power in the equal-diameter earlier stage; in the later stage of shouldering, dynamic switching from'low crucible rotation + vacancy type 'to'high crucible rotation + low power' in the earlier stage of equal diameter is carried out, so that vacancy type point defects are driven to move towards a V / I boundary (namely the area where an OSF ring is located) or even from the gap type side, and a clean area without an OSF nucleus is formed in a crystal.