3249results about "By pulling from melt" patented technology

The invention relates to a monocrystalline silicon thermal field multi-section dynamic cooperative heating control method and system, and the method comprises the following steps: constructing a thermal field multi-section temperature coupling model, dividing a thermal field into n axial heating sections, and building a dynamic relation between power input and temperature gradient; a deep reinforcement learning agent is designed, the state space of the deep reinforcement learning agent integrates the temperature of each heating section, the crystal lifting speed, the crucible lifting speed and the temperature gradient, and the action space outputs the power adjusting quantity of each heating section; defining a multi-target reward function, and jointly optimizing temperature gradient tracking, total power change and crucible bottom safety threshold; training the intelligent agent offline based on the thermal field model, and optimizing the strategy network; an intelligent agent is deployed online, and a power adjusting instruction is generated in real time; the control strategy is dynamically corrected, and online fine adjustment is performed through setting trigger adjustment. According to the method, the defects of a traditional method in the aspects of temperature gradient control precision, energy consumption economy and abnormal working condition self-adaptability are overcome, and the growth quality and efficiency of monocrystalline silicon are remarkably improved.

The present application relates to the technical field of carbon / carbon composite materials, and specifically discloses a carbon-carbon guide tube and a preparation method thereof. The preparation method of the carbon-carbon guide tube comprises: cutting carbon fibers into short fibers, combing the short fibers into a mesh; immersing the mesh into an impregnation liquid in the equipment to obtain a pre-impregnated mesh; laying multiple layers of impregnated mesh on the surface of a mold; curing the multiple layers of impregnated mesh on the mold, demolding to obtain a blank; carbonizing and graphitizing the blank; subjecting the graphitized blank to a chemical vapor deposition densification process and a pyrolytic carbon coating process in sequence to obtain a carbon-carbon guide tube. The method for preparing the carbon-carbon guide tube does not require the preparation of a preform, thereby eliminating the problem of carbon fiber waste generated during the manufacturing process of the preform, and can shorten the manufacturing cycle, improve production efficiency, and reduce production costs. The carbon-carbon guide tube prepared by the method has good mechanical properties and corrosion resistance, and can meet the use requirements of the guide tube for the thermal field of a photovoltaic direct-pull single crystal silicon furnace.

The invention relates to the field of Czochralski single crystal furnace crystal bar production, in particular to a Czochralski single crystal shouldering control system, which comprises a CCD (Charge Coupled Device) information acquisition unit, a computer information storage processing unit and a PLC (Programmable Logic Controller) growth regulation unit, the computer information storage processing unit receives information acquired by the CCD information acquisition unit, then performs cloud data storage processing and outputs single crystal shoulder information of a corresponding time node to the PLC growth regulation unit, and the PLC growth regulation unit performs shouldering cooling amount control, automatic crucible lifting intervention in the shouldering process, automatic intervention control of equal-diameter liquid opening distance and pulling speed control. According to the method, the problems of shouldering line breakage and equal-diameter head line breakage caused by the fact that automatic regulation of the current shouldering pulling speed does not conform to actual growth of crystals are solved, and the consistency of field process parameter management is improved.

The embodiment of the invention provides a Czochralski method crystal growth device and a regulation and control method, and relates to the technical field of crystal growth. The Czochralski method crystal growth device comprises a furnace body, a crucible, a first magnetic field device, a seed rod and a second magnetic field device, the crucible is arranged in the furnace body, and the first magnetic field device is arranged on the outer side of the crucible in a surrounding mode and located in the furnace body. The seed rod is arranged in the furnace body and is spaced from the crucible; the second magnetic field device is arranged on the seed crystal rod and is positioned in the furnace body; wherein the first magnetic field device is used for generating a magnetic field and acting on a melt in the crucible; the second magnetic field device is used for generating a magnetic field and acting on a growth interface of the melt. The Czochralski method crystal growth device can effectively inhibit convection of melt, so that solute distribution is uniform, and crystal defects are reduced; and the crystal structure can be optimized, and accurate regulation and control of solute are realized, so that the quality and the performance of the crystal are integrally improved.

Embodiments of the present disclosure provide a seed crystal holder and a crystal growth method. The seed crystal holder includes a seed crystal holder body and a connecting rod. The seed crystal holder body is fixed to one end of the connecting rod, and a seed crystal is provided on one side of the seed crystal holder body away from the connecting rod.

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 the technical field of crystal growth, in particular to a mold for growing a gallium oxide single crystal by an edge-defined film-fed growth method and a gallium oxide single crystal growth method. The mold is formed by connecting two partition plates through a fixing part, and a slit is reserved between the partition plates. Steps are arranged on the two radial sides of the top end of the mold, the bottom end of the mold is of an inverted trapezoidal structure, the two waists of a trapezoid are arc-shaped, and the bottom end of the mold is of an inverted trapezoidal structure, so that the temperature difference and temperature gradient of the surface of the mold are reduced, temperature distribution on the two sides of the mold is more symmetrical, and a more reasonable thermal field can be provided for size expansion of gallium oxide crystals.

The present invention provides a single crystal furnace and a single crystal silicon rod annealing method, the single crystal furnace comprises: a main chamber comprising a furnace body and a throat structure located above the furnace body which are connected with each other, and the furnace body is used for forming a single crystal silicon rod; the auxiliary chamber is mounted above the throat structure; the flow guide cover is arranged in the main chamber and located at the throat structure, the flow guide cover comprises a cover body, and the cover body is provided with a middle flow channel allowing the silicon single crystal rod to penetrate through and an annular flow channel surrounding the middle flow channel; the throat structure is provided with an inlet which is communicated with an inlet of the annular flow channel so as to introduce a first fluid into the annular flow channel; an inlet of the middle flow channel is communicated with the auxiliary chamber so as to receive a second fluid introduced from the auxiliary chamber; and an outlet of the annular flow channel is communicated with an outlet of the middle flow channel, so that the first fluid and the second fluid are converged to cool the monocrystalline silicon rod, and the problem that the minority carrier lifetime of monocrystalline silicon is easily shortened by a monocrystalline silicon annealing process in the prior art is solved.

The invention provides a process for preparing a silicon single crystal rod by a multi-feeding and multi-pulling method. The invention provides a process for preparing monocrystalline silicon by a multi-feeding and multi-pulling method for quantitatively compensating volatile doping elements in a re-feeding stage, which is a method for measuring and calculating the concentration of a volatile doping agent in a residual silicon melt in the re-feeding stage of the multi-feeding and multi-pulling method. Therefore, the purposes of accurately compensating the concentration of the volatile dopant and guaranteeing the quality consistency between crystal bars are achieved. According to the method, the concentration of the volatile dopant in the residual silicon melt in the re-feeding stage can be accurately measured under the condition that a crystal pulling furnace platform is not changed at all; the compensation amount of the volatile dopant in the re-feeding stage can be accurately obtained, and the stable quality of the crystal bar is ensured; meanwhile, auxiliary equipment is not needed, the method is low in cost, good in economical efficiency, suitable for various volatile dopants, wide in application range and suitable for an existing technology for preparing monocrystalline silicon through a multiple-feeding and multiple-pulling method, the technology does not need to be changed, and the production efficiency is high.

The invention discloses a phosphorus-antimony co-doped monocrystalline silicon rod, a preparation method and application, in the phosphorus-antimony co-doped monocrystalline silicon rod, the antimony element concentration is 2.3 * 10 < 16 > atoms / cm < 3 >-1.17 * 10 < 14 > atoms / cm < 3 >, and the phosphorus element concentration is 7.66 * 10 < 15 > atoms / cm < 3 >-3.9 * 10 < 13 > atoms / cm < 3 >. According to the embodiment of the invention, the silicon single crystal rod is doped with the phosphorus element and the antimony element at the same time, and when only the phosphorus element is doped in the silicon single crystal rod, the resistivity of the obtained silicon single crystal rod is usually high at the head and low at the tail; when only the antimony element is doped in the single crystal silicon rod, due to the fact that antimony is extremely volatile, the controllability of antimony doping in the preparation process is relatively low, and the resistivity is prone to occurrence of the conditions that the head is low and the tail is high, and therefore the difference of the resistivity of the single crystal silicon rod can be reduced through co-doping of phosphorus and antimony in the implementation mode of the application.

The invention belongs to the technical field of single crystal growth equipment, and particularly relates to a seed crystal clamping assembly, in particular to a seed crystal pulling assembly, a silicon carbide single crystal growth device and a use method of the silicon carbide single crystal growth device. The seed crystal lifting assembly comprises a lifting rod and a lifting rod, a rotating head; wherein a cavity is formed in the wall body of the rotating head, and a groove is formed in the middle of the rotating head; and fan blades are fixedly arranged in the grooves. The fan blades are arranged in the rotating head, the unique airflow channel is designed, the lifting rod rotates to drive the fan blades to work, and forced airflow circulation is formed, so that the problem that the radial temperature difference of a crystal growth face is large is solved, back heat dissipation of seed crystals is remarkably improved, and the interface stability of crystal growth is improved. And meanwhile, the growth speed can be directly regulated and controlled in time by adjusting the rotating speed of the lifting rod, so that the growth efficiency and the crystal quality are synergistically improved.

The invention relates to a temperature regulation and control method for a sapphire crystal growing furnace, the temperature regulation and control method is applied to the sapphire crystal growing furnace, the sapphire crystal growing furnace comprises a heat preservation structure, the heat preservation structure comprises at least two heat preservation units, and the heat preservation units are annular and stacked to form a cylindrical heat preservation structure; a medium cavity is formed in each heat preservation unit and used for containing a gas heat preservation medium. The number of the circulating units is the same as that of the heat preservation units, the circulating units are in one-to-one correspondence with the heat preservation units, and the circulating units are correspondingly connected with one heat preservation unit; in the first stage of crystal growth, gas heat preservation media with the same content are injected into the medium cavities of all the heat preservation units; in the second crystal growth stage, the content of the gas heat preservation medium in the medium cavity is gradually reduced in the direction from bottom to top. The technical problem that the sapphire crystal growth quality is poor is solved, and the technical effect of improving the sapphire crystal growth quality is achieved.

The invention relates to the technical field of monocrystalline silicon manufacturing, provides a manufacturing method of a monocrystalline silicon rod and a silicon wafer, and at least facilitates the control of the resistivity uniformity of the monocrystalline silicon rod. The method comprises the steps that a test single crystal silicon rod is prepared, an initial doping concentration model is simulated according to the test single crystal silicon rod, and the initial doping concentration model is characterized in that in the equal-diameter process, the change trend of the concentration of a doping agent in the test single crystal silicon rod along with time is tested; the initial doping concentration model is optimized according to the target concentration interval to obtain a prediction model, the prediction model represents the variation trend of the concentration of the doping agent in the single crystal silicon rod along with time under the condition of multiple times of doping agent supplementation in the equal-diameter process, the prediction model comprises multiple concentration inflection points and multiple doping supplementation time points, and the concentration inflection points are different from the doping supplementation time points; each supplementary doping time point is correspondingly prior to a concentration inflection point; and preparing a target single crystal silicon rod, and in the equal-diameter process of preparing the target single crystal silicon rod, supplementing the dopant according to the supplementing time point.

A differential lifting / lowering device for multiple circles of seed crystals and a method for the differential lifting / lowering of multiple circles of seed crystals. The device comprises: a seed crystal holding mechanism provided with multiple circles of holders for holding seed crystals; at least one lifting / lowering mechanism for driving at least one circle of holders to perform lifting / lowering motion; and a control device for controlling the speed of the at least one lifting / lowering mechanism on the basis of a diameter change obtained from the diameter of at least one crystal rob among crystal rods generated by the circles of seed crystals held by the seed crystal holding mechanism.

The high-frequency heating device includes at least a phase difference detector, a frequency controller, an inverter, and an LCR circuit, and the phase difference detector detects the phase difference between the high-frequency voltage generated by the frequency controller and the high-frequency current flowing through the LCR circuit, and the inverter updates the driving frequency of the high-frequency voltage based on the phase difference to control the current in the LCR circuit.

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 present invention relates to the technical field of gallium oxide crystal growth, and in particular to a thermal field structure and a device and method for preparing gallium oxide single crystals based on a guided mold method. The present invention changes the inner cavity at the bottom of the thermal field structure from a circular cavity to an elliptical cavity, so that the thermal field structure in the width direction of the mold extends toward the mold side, thereby improving the thermal insulation of the thermal field structure on both sides of the mold, and then prompting the mold core to move closer to the edges on both sides of the mold, ensuring the constant temperature gradient on the mold surface during the shouldering process of the crystal, avoiding temperature differences, and improving production efficiency. In addition, since the extended thermal field structure will make the air inlet airflow closer to the mold surface, resulting in the problem of cold airflow directly blowing the crystallization area on the mold surface, a drainage port is added below the air inlet to guide the cold airflow to the crucible position, thereby ensuring the effect of the mold core moving closer to the edges on both sides of the mold.

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 combined crucible and an oxide crystal growth method.The combined crucible is used for oxide crystal growth and comprises a first ceramic crucible, a second ceramic crucible, a third ceramic crucible and a fourth ceramic crucible, the graphite layer is arranged in the first ceramic crucible; the second ceramic crucible comprises a second containing space with the top open and the bottom closed, and the second ceramic crucible is arranged in the graphite layer. The combined crucible is designed by adopting an iridium-free scheme, so that the cost of the crucible can be greatly reduced.

This application provides a crystal growth method and crystalline silicon, relating to the field of solar photovoltaic technology. The method comprises: performing a leak test on a single crystal furnace under a first furnace pressure; adding a dopant to the single crystal furnace under a second furnace pressure; wherein the second furnace pressure is greater than the first furnace pressure; and performing a crystal pulling process after adding the dopant. This application can reduce axial concentration distribution differences of doping elements in doped single crystal silicon, improve axial resistivity uniformity of the single crystal silicon, and enhance production efficiency.

The invention relates to the technical field of electronic materials and devices, in particular to a preparation method of a miniature transverse wave piezoelectric micromechanical ultrasonic transducer based on x-cut single crystal lithium niobate and a transverse wave probe, and the method comprises the following steps: carrying out growth and x cutting on lithium niobate crystals to obtain a self-polarized lithium niobate wafer; carrying out graphical processing on the self-polarized lithium niobate wafer; cutting the self-polarized lithium niobate wafer subjected to graphical processing based on a preset tangential angle to obtain lithium niobate wafer slices at different tangential angles; and preparing the transverse wave probe by using the lithium niobate wafer slices at different tangential angles. The invention aims to realize preparation of a PMUT transverse wave device and solve the limitation that a traditional transverse wave probe is large in size and difficult to array and integrate.

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 utility model discloses a thermal field structure for X-cut lithium niobate crystal growth, the X-axis is defined to extend upwards, the thermal field structure comprises a thermal insulation structure and a crucible, both the thermal insulation structure and the crucible are elliptical cylinders with open upper ends and closed lower ends, when the thermal field structure is used, the crucible is placed in the thermal insulation structure, the central axes of the crucible and the thermal insulation structure coincide, and the central axes of the crucible and the thermal insulation structure coincide. The heat preservation structure is provided with a long axis a1 and a short axis b1, the crucible is provided with a long axis a2 and a short axis b2, the long axis of the heat preservation structure and the long axis of the crucible both extend in the Y-axis direction, the short axis of the heat preservation structure and the short axis of the crucible both extend in the Z-axis direction, and the grown lithium niobate crystal is an elliptic cylinder. According to the utility model, the problem that the crystal is easy to crack in the prior art is solved, and the success rate of the growth of the X-axis lithium niobate crystal is improved.

The invention provides a czochralski silicon single crystal growth process multivariable monitoring method, and belongs to the technical field of czochralski silicon single crystal growth. Comprising the following steps: synchronously acquiring and pre-processing various process variable time sequence data in a czochralski silicon single crystal growth process to obtain a multivariable time sequence matrix; performing slow feature extraction on the multivariable time sequence matrix by using a multi-scale sliding window strategy, and sequentially constructing a static slow feature matrix and a dynamic slow feature matrix; the static slow feature vector and the dynamic slow feature vector of each time step are spliced into a fusion slow feature vector, all the fusion slow feature vectors form a fusion slow feature matrix, and the fusion slow feature matrix is divided into a fusion training set and a fusion test set; and constructing an auto-encoder network model, and training and testing the auto-encoder network model to obtain a multivariable monitoring result. According to the invention, accurate real-time monitoring of the growth process of the czochralski silicon single crystal in a complex environment can be realized.

The invention discloses a high-precision liquid level moving position measuring assembly and method, and the assembly comprises a crucible which is filled with a silicon liquid; the guide cylinder is arranged above the silicon liquid, and a high-temperature-resistant component is arranged at the bottom of the guide cylinder; the crystal bar cooling device is arranged above the silicon liquid, the crystal bar cooling device is arranged in the guide cylinder, and a plurality of crystal pulling holes are formed in the bottom of the crystal bar cooling device; the camera is used for acquiring the high-temperature-resistant component and the image of the inverted image of the high-temperature-resistant component on the silicon liquid level; the controller is used for receiving and processing data transmitted by the camera; a protrusion is arranged on the high-temperature-resistant component, and a through hole is formed in the protrusion. The high-precision liquid level moving position measuring assembly and the measuring method are convenient to use, through camera measurement and controller control, the moving positions of the bottom of a crystal bar cooling device and the liquid level of raw material silicon liquid are measured and controlled in real time, and therefore the diameter of a crystal bar can be controlled.

The invention belongs to the field of process dust removal in industrial production of monocrystalline silicon, polycrystalline silicon, heavily doped silicon single crystal and the like, and particularly relates to a crystal pulling oxygen-free ash conveying system. Aiming at the problems that the resistance of a filter bag of an existing simple harmonic dust collector is gradually increased, the quality of a crystal bar and the power consumption of rear-end equipment are seriously influenced, for example, the crystallization rate is reduced, the original crystal rate is reduced, the original crystal per unit yield is reduced and the oxygen content is increased, the following scheme is provided. The device comprises a crystal pulling furnace L located at the front end of the process, a simple harmonic dust collector A used for filtering and collecting impurities generated in the crystal pulling process, and an ash conveying pipeline B. Through automatic control, double cleaning of rapping and back flushing is carried out on a filter bag of the simple harmonic dust collector, vacuum pipeline ash discharging operation is carried out on an ash bin of the simple harmonic dust collector, and passivation treatment of dust is carried out. The safety and sustainability of production are guaranteed, the product quality is improved, the energy consumption of enterprises is reduced, the production efficiency is improved, conditions are provided for realizing continuous crystal pulling, and a step is made for the enterprises to realize intelligent factories.

The invention discloses a silicon single crystal growth interface deformation detection method, system, equipment and medium, and relates to the technical field of silicon single crystal growth soft measurement modeling. Comprising the following steps: acquiring a process parameter set in a silicon single crystal production process; the process parameters in the process parameter set serve as nodes, mutual information indexes between the nodes serve as edges, and a graph structure model is constructed; performing multi-layer neighborhood aggregation operation on the graph structure model to obtain initial features; performing attention mechanism operation on the initial features to obtain aggregated features; and carrying out weighting operation on the aggregation characteristics by adopting a long-short-term memory network to obtain a deformation detection result of the silicon single crystal growth interface. According to the method, the modeling expressive power of a complex dynamic process is improved, and the sensitivity and the response speed of an abnormal deformation evolution trend are also remarkably enhanced.

A crystal growth method and system, an apparatus, and a storage medium. The crystal growth method comprises: determining a parameter set of a crystal growth device in a target heat, wherein the parameter set comprises at least one target parameter, and the target parameter is a parameter, affecting crystal growth, in the crystal growth device; acquiring a first temperature measurement value of a first temperature measurement point of the crystal growth device in a target time period of the target heat; and on the basis of the target parameter and the first temperature measurement value, by means of a crystal plane temperature determination model, determining a simulated crystal plane temperature corresponding to the first temperature measurement value.

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.

In a first step S101, the raw material is directly induction heated using a high-frequency induction heating coil (103) while cooling the outer periphery of a raw material (151) to or below the melting point of the raw material by a cooling mechanism (102) to form a raw material melt (152) (raw material melting step). In a second step S102, a seed crystal (161) is brought into contact with the melt (seeding step). In a third step S103, a crystal (153) is grown from the seed crystal (crystal growth step). In the third step S103, the high-frequency induction heating coil and the seed crystal are gradually separated from each other while maintaining the relative distance between the high-frequency induction heating coil and the outer periphery of the raw material, and the crystal is grown in the melt.