10043results about "Polycrystalline material growth" patented technology

Crystal growth systems with a baffle are provided. In one example, a crystal growth system for growing crystalline material, the crystalline material including silicon carbide, includes a seed holder configured to hold a silicon carbide seed crystal. The seed crystal provides a growth surface for growth of the silicon carbide crystalline material. The system includes a crucible at least partially defining a crystal growth chamber. The system includes a source material. The system includes one or more baffles within the crystal growth chamber and spaced apart from the source material. The one or more baffles include one or more apertures defined through the one or more baffles. The baffle includes a long dimension that is non-perpendicular to the growth surface of the seed crystal.

The invention belongs to the technical field of silicon carbide single crystal materials, and particularly relates to a growth device of large-size silicon carbide single crystals and a preparation method of the silicon carbide single crystals, porous graphite cylinders are arranged in a powder area of the growth device of the large-size silicon carbide single crystals, and the porous graphite cylinders are distributed along the edge of the powder area to the center in a stepped mode. The height is gradually increased from the edge to the center; a plurality of layers of stacked graphite pore plates are arranged at the top of the powder area, the upper end parts of the porous graphite cylinders are flush with the upper surfaces of the corresponding layers of graphite pore plates, and the porous graphite cylinders penetrate through the graphite pore plates, so that a continuous gas phase transmission channel from the powder area to the crystal growth area is formed. According to the invention, the plurality of porous graphite cylinders are arranged in the silicon carbide raw material area in a stepped manner, so that the temperature field distribution of the raw material area is stabilized, the gas phase layout is optimized, impurities in gas phase components are filtered, and the defects of microtubes, inclusions, dislocation and the like in crystals are improved.

The invention relates to the technical field of crystal material preparation, in particular to a ternary layered selenide Ge3Sb4Se7 semiconductor material and a preparation method thereof. The preparation method of the ternary layered selenide Ge3Sb4Se7 semiconductor material comprises the following steps that S001, germanium powder, antimony powder and selenium powder with the molar ratio being 3: 4: 7 serve as raw materials, the temperature is increased to 900-950 DEG C under the vacuum condition, and heat preservation is conducted for 12-24 h at the temperature; s002, after heat preservation is finished, the temperature is reduced to 475-500 DEG C at the cooling rate of 1-5 DEG C / min, and heat preservation is conducted for 3-5 days at the temperature; and after heat preservation is finished, furnace cooling or quenching cooling is performed to reach the room temperature, and the layered ternary selenide single-phase material with the chemical formula being Ge3Sb4Se7 is obtained. The ternary layered selenide Ge3Sb4Se7 semiconductor material prepared by the invention is a single-phase material and has the characteristics of low thermal conductivity and low resistivity, so that the ternary layered selenide Ge3Sb4Se7 semiconductor material has application potential in the fields of thermoelectric devices, photoelectric detection and the like.

The invention discloses a series of alkali metal borate compounds and alkali metal borate crystals as well as a preparation method and application thereof, and belongs to the technical field of photoelectric functional crystal materials. The chemical general formula of the series of compounds and crystals thereof is A3RE (B3O6) 2, wherein A is K, Rb, Cs or NH4; rE = Sc and Y, the molecular weight is 355.93-744.48, the series of crystals belong to a trigonal system, the space group is P321, the cell parameters a = b = 10.5237 (13)-135237 (13), and # imgabs0 # Z = 3. The series of alkali metal borate compounds are synthesized by adopting a solid-phase reaction method or a hydrothermal method, and the series of crystals grow by adopting a high-temperature melt method or a hydrothermal method or a solution method. The series of materials can be used for manufacturing second harmonic generators, upper and lower frequency converters, optical parametric oscillators, polarizing prisms and the like.

A silicon carbide source material structure for use in a sublimation system for growing single crystal silicon carbide is provided. The silicon carbide source material structure may comprise a first layer and a second layer, the first layer being different from the second layer in at least one property.

The invention provides a vertical structure ultraviolet photoelectric detector and a preparation method thereof. The ultraviolet photoelectric detector is of a vertical structure, the design facilitates light absorption of the ultraviolet photoelectric detector, the light utilization rate of the ultraviolet photoelectric detector is improved, and compared with a horizontal structure, the transmission distance is shortened, and the cost is low; the ultraviolet photoelectric detector provided by the invention has a relatively high switching ratio of light and dark current and relatively small dark current, and also has a very high response speed under the condition of keeping the switching ratio of light and dark current and the dark current; a PN junction is formed between the nickel oxide hole transport layer and the beta-phase gallium oxide single crystal, so that the ultraviolet photoelectric detector has self-driving performance; in the manufacturing process, the substrate is used as a supporting frame, and the extraction electrode is packaged in one step through the conductive adhesive tape, so that 3-5 photoetching steps of a traditional horizontal structure are omitted, the process is simplified, and the process manufacturing is simpler.

The invention discloses a method for realizing high-quality stripping of large-size diamond by double-laser composite modification, which comprises the following steps: placing and fixing a sample on a three-dimensional mobile platform, and the upper surface of the sample is a crystal face (100); laser generated by an ultrafast laser generator penetrates through the upper surface of a sample and is focused into the sample, and then the laser generated by the ultrafast laser generator is used for performing first spot scanning on the sample to form an independent lattice structure; laser generated by the ultrafast laser generator is adopted to carry out secondary spot scanning on the sample to form a crack interconnected lattice structure; performing third-time line scanning on the sample by using laser generated by a nanosecond laser generator; and ultrasonically stripping the sample in water bath. By adopting a dual-laser composite modification process and combining bionic'honeycomb 'and'turtle shell' crack structure design, the crack is effectively guided to directionally extend along the crystal face (100), the problem of oblique crack when the stripping face is the crystal face (111) in the past is avoided, and the integrity and flatness of the stripping face are greatly improved.

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 preparation method of a barrier type antimonide infrared detector. The preparation method comprises the following steps: selecting a gallium antimonide substrate; a gallium antimonide buffer layer, an indium arsenide heavily-doped layer, a class II superlattice absorption layer and an aluminum-arsenic-antimony barrier layer are sequentially grown on the substrate in an epitaxial mode through a molecular beam epitaxy method; mechanically stripping the hexagonal boron nitride two-dimensional material, and transferring the stripped hexagonal boron nitride to the aluminum-arsenic-antimony barrier layer to form a Van der Waals heterojunction and composite barrier layer structure; depositing electrodes by using an ultraviolet lithography technology and a thermal evaporation mode to form one electrode arranged on the gallium antimonide buffer layer and the other electrode arranged on the boron nitride; a large-numerical-aperture micro-lens array is processed on a substrate, and the micro-lens array is composed of gallium antimonide cylinders with a phase modulation function; therefore, the antimonide medium-wave infrared detector with the composite barrier layer can be formed, the quantum efficiency is improved, the order of magnitude of dark current is reduced, and room-temperature medium-wave infrared detection can be realized.

The present invention relates to a positive electrode material including a plurality of single particle-based positive electrode active material particles, wherein the single particle-based positive electrode active material particle includes 1 to 30 primary particles, the product of an arithmetic mean value of the circularities of the primary particles and an arithmetic mean value of the convexities of the primary particles, which are measured from the segmentation image partitioned for each primary particle unit obtained by image-processing a scanning electron microscope (SEM) image of the positive electrode material, is at least 0.60, the circularity is defined by Equation 1 below, the convexity is defined by Equation 2 below, and the single particle-based positive electrode active material includes a lithium nickel-based oxide having a composition represented by Formula 1 below: Circularity=4πA / P2 wherein, in Equation 1 above, A is the area of each primary particle measured from the segmentation image, and P is the circumference of each primary particle measured from the segmentation image, Convexity=Pc / Pr wherein, in Equation 2 above, Pr is the actual circumference of each primary particle measured from the segmentation image, and Pc is the circumference of a virtual figure obtained by connecting the outermost points of each primary particle measured from the segmentation image, and         [Formula 1]     Lia[NixCoyM1zM21-x-y-z]O2 wherein, in Formula 1 above, M1 includes Mn, Al, or a combination thereof, M2 includes at least one selected from the group consisting of B, Ba, Ce, Cr, F, Mg, Al, V, Ti, Fe, Zr, Zn, Si, Y, Nb, Ga, Sn, Mo, W, P, and Sr, 1.0≤a≤1.3, 0.5≤x<1.0, 0<y<0.5, and 0<z<0.5.

The invention provides an anti-ferroelectric lanthanum ferrite, bismuth ferrite and strontium titanate superlattice film with high energy storage density as well as a preparation method and application thereof. The anti-ferroelectric lanthanum ferrite, bismuth ferrite and strontium titanate superlattice film with high energy storage density comprises a substrate layer, a bottom electrode layer and a plurality of stacked relaxation ferroelectric layers, wherein the bottom electrode layer and the multiple stacked relaxation ferroelectric layers are sequentially arranged on the substrate layer; each relaxor ferroelectric layer sequentially comprises a first functional layer, a second functional layer and a third functional layer from bottom to top; the first functional layer comprises LaFeO3, the second functional layer comprises BiFeO3, and the third functional layer comprises SrTiO3. The anti-ferroelectric lanthanum ferrite, bismuth ferrite and strontium titanate superlattice thin film with the high energy storage density has small electric leakage performance and high polarization value, and more excellent energy storage performance is achieved.

The invention relates to a chip integrated heat dissipation system and a preparation method thereof, and belongs to the technical field of heat dissipation of semiconductor devices. The chip integrated heat dissipation system comprises a nano-diamond transition layer attached to a chip. A micro-column array supporting layer is arranged on one side, far away from the chip, of the nano-diamond transition layer; the micro-column array supporting layer is in contact with one surface of the diamond film, and the other surface of the diamond film is attached to the three-dimensional micro-channel heat dissipation layer. The invention also provides a preparation method of the chip integrated heat dissipation system. The chip integrated heat dissipation system provided by the invention has the advantage of efficient heat dissipation, and through the combination of the three-dimensional structure and the high heat conduction characteristic of diamond, the heat dissipation power density is remarkably improved, the junction temperature of the chip is reduced, and the heat dissipation requirement of a high-power device is met. The heat dissipation performance reliability is high, the thermal stress is eliminated through the gradient structure design, the interlayer binding force is improved, and the stable performance is still kept after multiple thermal cycles. And the preparation process is good in compatibility and convenient for large-scale production.

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 discloses a diamond film and a preparation method and application thereof, and the preparation method comprises the steps: taking a substrate material matched with the lattice constant of a diamond film material as a substrate, and carrying out the surface treatment of the substrate; mixed reaction gas comprising 80%-95% of hydrogen, 3%-8% of methane and 2%-12% of auxiliary gas is introduced, wherein the auxiliary gas comprises at least one of argon, chlorine, hydrogen fluoride and hydrogen chloride; carrying out controlled chemical vapor deposition at 850-1000 DEG C under the pressure of not less than 21 kPa, and growing a diamond film on the surface of the substrate; and annealing the diamond film. According to the method, chemical vapor deposition is controlled through cooperation of auxiliary gas and temperature-pressure gradient, and non-corrosion high-speed growth of the high-purity monocrystal diamond film is achieved; in combination with a dynamic annealing process, lattice defects are effectively repaired, the comprehensive performance is optimized, and the reliability of the thin film serving as a heat dissipation component and other applications is remarkably improved.

The present invention relates to a positive electrode material comprising a plurality of single-particle-based positive electrode active material particles, each of which includes 1 to 30 primary particles, wherein the arithmetic average value of tortuosity of the primary particles as measured from a segmentation image divided for each primary particle unit, obtained by image processing of a scanning electron microscope (SEM) image of the positive electrode material, is 0.92 or greater, and the tortuosity is a value defined by equation (1). Equation (1): Tortuosity =Pc / Pr, where Pr is the real length of the perimeter of each primary particle measured in the segmentation image, and Pc is the length of the perimeter of a conceptual figure obtained by connecting outermost points of each primary particle measured in the segmentation image.

A silicon carbide source material structure for use in a sublimation system for growing crystalline silicon carbide is provided. The silicon carbide source material structure includes a composite shaped solid. The composite shaped solid may be made by casting, extrusion, 3D printing, graphite conversion, or other suitable process.

The invention provides a method for preparing an iron-based superconducting material single crystal in a microgravity environment, and belongs to the field of superconducting materials. The method specifically comprises the following steps: carrying out a microgravity crystal growth experiment in a high-temperature experiment cabinet of a space station, putting a solid-phase sintered or pre-melted rod-like raw material into a furnace body, heating and melting, then slowly solidifying, and finally growing the iron-based superconducting material single crystal with large size and extremely low defect density.

The invention relates to the technical field of diamond growth, and provides a preparation method of a polycrystalline diamond wafer and the polycrystalline diamond wafer, the method comprises the following steps: providing a sample with a first surface and a second surface opposite to each other, and pre-growing a first polycrystalline diamond layer on the first surface of the sample; the sample is placed on a molybdenum sheet table in chemical vapor deposition equipment, the first polycrystalline diamond layer faces the molybdenum sheet table, a second polycrystalline diamond layer grows on the second face of the sample, the sample is formed, and the thickness of the second polycrystalline diamond layer is larger than that of the first polycrystalline diamond layer; and separating the second polycrystalline diamond layer from the sample to obtain the polycrystalline diamond sheet. According to the polycrystalline diamond wafer prepared by the method, the warping control and the thickness uniformity are remarkably improved, the yield of finished products is high, the processing efficiency is high, and the production cost is low.

The invention relates to a method for improving epitaxial growth quality of a tunnel junction cascade semiconductor laser. The invention innovatively provides a strain superlattice gradient repair technology. By designing a low-temperature low-speed nucleation-high-temperature high-speed epitaxy composite growth mode, a periodic superlattice buffer layer is introduced to a tunnel junction interface. Wherein lattice strain relaxation is achieved at the rate of 0.5-2 / s in the low-temperature stage, defect coverage is completed at the rate of 4-8 / s in the high-temperature stage, and dislocation line bending is terminated on a superlattice interface through thermodynamic regulation and control. Compared with the traditional process, the scheme can obviously improve the crystal quality, and does not increase the specific contact resistance of the tunnel junction interface.

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 discloses a super-large-scale silicon single crystal growth method based on a high-temperature superconducting magnetic control technology, and relates to the technical field of silicon single crystal growth, and the method comprises the following steps: setting and calibrating an initial magnetic field intensity, and combining a gradient graphite felt heat conductivity coefficient function to optimize temperature field uniformity; a dynamic magnetic field regulation and control mechanism is introduced in the melt stage, melt convection is inhibited through flow velocity-magnetic field joint control, and oxygen concentration monitoring is synchronized; a multi-physics coupling simulation and multi-objective optimization algorithm is adopted in the crystal growth stage, the magnetic field intensity, the heating power and the crystal pulling parameters are adjusted in real time, and the oxygen content and the growth rate are balanced; and the tail stress is relieved through a gradient field reduction technology, and finally, the low-defect and high-uniformity silicon single crystal is obtained. Melt flow and temperature field uniformity are accurately regulated and controlled through a high-temperature superconducting magnetic control technology, dynamic monitoring and a multi-target optimization algorithm are combined, the growth quality of silicon single crystals is remarkably improved, the defect rate and energy consumption are reduced, and meanwhile efficient and stable production of large-size crystals is achieved.

The invention relates to the technical field of semiconductor equipment, and provides vertical epitaxy equipment and an epitaxy method. The apparatus comprises: a vertical reaction chamber; the wafer boat is used for vertically loading a plurality of wafers at intervals; the driving device is used for driving the boat to enter / exit the vertical reaction cavity; the material supply assembly comprises a process supply pipeline and a switching unit; the process material source comprises a cleaning material source for removing an oxide layer on the surface of the wafer and an epitaxial material source for executing an epitaxial process; the process monitoring device is used for monitoring process end points of the cleaning process and the epitaxial process; and the control device is in communication connection with the switching unit and the process monitoring device, and controls the switching unit to switch the supply of the material source according to the monitoring result of the process monitoring device. According to the vertical epitaxial equipment, the epitaxial process can be continuously executed without transferring the wafers after the oxide removal process of the plurality of wafers is executed in situ in the equipment, so that the output rate and the yield of the equipment are improved, the cost is reduced, and the fragment and pollution risks are reduced.

The invention relates to a gallium oxide epitaxial layer prediction method and device, equipment and a medium, and the method comprises the steps: collecting the technological parameters of MOCVD and the characterization data of an epitaxial layer, and carrying out the data preprocessing, and obtaining the preprocessed data; performing feature derivation and feature screening on the preprocessed data, and performing data set division on the data after feature screening to generate a training data set and a test data set; constructing an XGBoost regression model, and performing hyper-parameter search to obtain a target optimal parameter combination so as to train the XGBoost regression model and generate a trained XGBoost regression model; testing the trained XGBoost regression model through the test data set to generate a target XGBoost regression model; to-be-measured process parameters of MOCVD are obtained, and epitaxial layer prediction is carried out on the to-be-measured process parameters to obtain the target epitaxial layer thickness and the target full width at half maximum variation. The prediction accuracy of the gallium oxide epitaxial layer is improved.

The invention relates to the technical field of polycrystalline silicon deposition used as a main raw material in the semiconductor or solar industry, in particular to a polycrystalline silicon deposition air inlet device based on growth characteristics of a silicon core rod and a control method. The control method comprises the following steps: determining growth abnormal area data of the silicon core rod and overall growth rate data of the silicon core rod based on the surface temperature distribution uniformity degree of the silicon core rod in a first preset time length and / or the growth uniformity degree of the silicon core rod in a second preset time length; determining to control air intake by a local control method or an integral control method based on whether the growth abnormal area with the non-overlapped area and the growth abnormal area after space splicing cover the silicon core rod for a circle or not and a comparison result of the integral growth rate of the silicon core rod and a preset integral growth rate; according to the invention, the control accuracy of the air inlet device is improved by improving the analysis accuracy of the growth characteristics of the silicon core rod.

An object of the present invention is to provide a novel technique capable of manufacturing a large-diameter AlN substrate.The present invention is a method for manufacturing an AlN substrate, including a crystal growth step S30 of forming an AlN layer 20 on a SiC underlying substrate 10 having through holes 11. In addition, the present invention is a method for forming an AlN layer including the through hole formation step S20 of forming the through holes 11 in the SiC underlying substrate 10 before forming the AlN layer 20 on the SiC underlying substrate 10.

The invention provides a directional solidification preparation method of a degradable high-hardness zinc alloy material. The preparation method of the zinc alloy material comprises the machining processes of vacuum induction melting, vacuum directional solidification melting and the like, through the preparation method, growth of Zn + Mg2Zn11 trilobal eutectic and Zn + MgZn2 spiral eutectic is regulated and controlled, microscopic structures are arranged in the specific direction, fine and uniform structure morphology is formed, and the corrosion resistance and the mechanical property of the alloy are improved. The Zn-Mg series alloy prepared by the preparation method disclosed by the invention shows excellent microhardness (181.19 to 243.10 HV). Besides, the corrosion rate of the ideal degradable bone implant is within the range of 0.1 mm / y to 0.5 mm / y, and the corrosion rate of the degradable medical Zn-Mg alloy bone implant material is within the range of 0.0316 mm / y to 0.2280 mm / y, so that the requirement on the corrosion rate in the bone repair process is met; and after the Cu element is added on the basis of Zn-3% Mg, the microhardness of the Zn-3% Mg-Cu-Cu alloy material is improved to about 200HV, and the advantages in the aspect of mechanical support are improved.

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 belongs to the technical field of nickel-based single-crystal superalloy materials, and provides a nickel-based single-crystal superalloy and a strengthening method thereof, and the method comprises the following steps: cleaning and drying the nickel-based single-crystal superalloy to be strengthened; strengthening parameters and a shock strengthening path are set, and the nickel-based single crystal high-temperature alloy is subjected to absorption-layer-free laser shock strengthening; the strengthened nickel-based single crystal high-temperature alloy is cleaned and dried; polishing parameters and a polishing path are set, femtosecond laser oblique incidence polishing is conducted on the strengthened area of the nickel-based single crystal superalloy, and surface ablation is removed; the polished nickel-based single crystal high-temperature alloy is cleaned and dried; according to the method, the nickel-based single crystal superalloy is strengthened by adopting an absorption-layer-free laser shock strengthening mode, and femtosecond laser oblique incidence polishing is adopted, so that the procedures of pasting and removing an absorption layer for multiple times are avoided, the processing efficiency of laser shock strengthening is improved, and deterioration of the surface quality of a material caused by laser ablation is avoided.

The diamond coated glass structure may include a glass substrate in which the deposited nanocrystal diamond is coated on the glass substrate. A layer of ultra-nanocrystalline diamond may be deposited on the deposited nanocrystalline diamond. The combination of the deposited nanocrystal diamond and ultra-nanocrystal diamond may have a surface roughness of less than 9 nanometers RMS.

According to the large-size single crystal diamond structure and the preparation method thereof, at least two diamond seed crystals are embedded into the grooves penetrating through the metal iridium film layer and the yttria-stabilized zirconia layer in the thickness direction, so that the single crystal diamond epitaxial layer can be grown on the diamond seed crystals through the homoepitaxy technology; meanwhile, the monocrystal diamond epitaxial layer is grown on the metal iridium body between the diamond seed crystals by utilizing a heteroepitaxy technology, so that the quality of the corresponding monocrystal diamond epitaxial layer between the diamond seed crystals can be improved; the problem that in the prior art, a splicing growth technology is adopted to obtain a large-size single crystal diamond epitaxial layer, steps or defects appear at splicing seams is solved, and therefore the large-size and high-quality single crystal diamond epitaxial layer can be obtained through the homoepitaxy and heteroepitaxy combined growth mode.