27 results about "Lattice strain" patented technology

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 application integrates a passive wireless temperature control sensing unit and a pulse eddy current nondestructive testing module, synchronously collects temperature, frequency offset and lattice strain data of a low-temperature bearing ring under rotating working conditions, constructs a thermal-force coupling correlation model through a low-temperature tribology-thermal conduction coupling analysis module, and outputs a friction heat generation rate prediction value. Relying on a federal learning edge inference module, distributed model training is completed, combined with homomorphic encryption to guarantee data security, and the data island restriction is broken through. Based on an optimization strategy, the edge controller dynamically adjusts the sensing sampling interval through reinforcement learning, solves a multi-objective optimization problem by using a non-dominated sorting genetic algorithm, and drives the hierarchical start and stop of the self-cooling system. The application eliminates the physical interference of wired sensing, realizes adaptive temperature control and energy-saving cooling of the bearing ring under low-temperature working conditions, and improves the temperature control precision and system generalization ability.

This invention discloses a phase-field method for controlling creep microstructure through lattice strain using an interface-based input / output system. This method provides a visual input / output interface, enabling direct input / output of parameters and computational data. By establishing a dual-sublattice thermodynamic model coupled with a crystal phase-field kinetic model, and setting initial kinetic and thermodynamic parameters, the creep microstructure morphology is controlled by altering the coherent mismatch degree between the precipitated phase and the matrix phase, as well as the magnitude of external stress and strain. This invention, while enabling control of creep microstructure morphology, also includes a visual operating interface, making the computer simulation process more convenient and efficient. The combination of the crystal plastic phase-field method and the operating interface module yields rich simulation results, providing theory and methods for establishing the relationship between creep microstructure and strain in high-temperature alloys, as well as for the optimization design of microstructure control.

The invention relates to a method for inducing optical anisotropy of a crystal material through heavy ion irradiation. According to the method, ion irradiation is carried out on an area, perpendicular to the in-plane crystal orientation, of a crystal material, so that defect aggregation and a lattice strain field are introduced into the area, and ion irradiation induces refractive index changes which are different in the in-plane direction and the out-of-plane direction in the area, so that an optical anisotropic structure is formed; ions adopted in the ion irradiation are Xe31 + ion beams. By controlling the ion dosage and utilizing the structural anisotropy of the rutile crystal, differentiated refractive index changes are successfully induced in the in-plane direction and the out-of-plane direction, strong and directional optical anisotropy is achieved, and a foundation is laid for manufacturing polarization-sensitive photonic devices.

The invention provides a silicon carbide epitaxial structure and a preparation method thereof, and belongs to the technical field of semiconductors, and the silicon carbide epitaxial structure comprises a silicon carbide substrate, a gradient buffer layer, a growth interruption region, a conventional buffer layer and a drift layer which are sequentially arranged from bottom to top; the gradient buffer layer and the growth interruption region generate lattice strain by means of a doping concentration gradient change to reduce base plane dislocation and stacking fault density. According to the silicon carbide epitaxial structure provided by the invention, a gradual change buffer layer formed by interface modulation doping is arranged on a silicon carbide substrate, and a growth interruption region is formed on the gradual change buffer layer by a growth interruption process; the gradient buffer layer is formed in a doping concentration gradient mode, lattice strain and lattice stress between the substrate and the drift layer are modulated, the base plane dislocation density and stacking fault density of an epitaxial wafer are effectively reduced, and the quality of a silicon carbide epitaxial structure is remarkably improved.

The invention relates to the technical field of gallium nitride power device electron mobility detection scheme design, in particular to a gallium nitride power device electron mobility detection method and system. The method comprises the following steps of: synchronously measuring an electrical response signal of a device and an optical response signal of a channel region under the conditions of set electrical stress (such as high-frequency switching pulse and high-current bias) and thermal stress (such as a high-temperature working condition); on the basis of optical signals, physical parameters such as carrier distribution, lattice strain and local temperature are analyzed, in combination with a preset 2DEG mobility calculation model, the mobility estimated by the electrical signals is corrected and compensated, and finally accurate electron mobility information is obtained. The system integrates a high-speed electrical test module, a microscopic optical acquisition module and a model resolving module, and realizes spatial resolution surveying and mapping of mobility and transient capture of a dynamic switch. According to the method, the problem of mobility test distortion under extreme working conditions is solved, and key technical support is provided for reliability and performance optimization of GaN power devices.

The present invention provides a light-emitting element capable of suppressing a degradation in reliability.　The light-emitting element according to the present technology comprises: a substrate; a laminated structure which is disposed on the substrate and in which a plurality of layers including a light-emitting layer are laminated; and an intermediate structure disposed between the substrate and the laminated structure and including a layer having a lattice strain. According to the light-emitting element according to the present technology, it is possible to provide a light-emitting element capable of suppressing a degradation in reliability.

This invention relates to the field of optical interferometry technology and discloses a multi-scale anisotropic dynamic elastoplastic mesh phase unpacking method and apparatus. The method involves obtaining the gradient field of the encapsulated phase matrix as the initial prestress; establishing a discrete node mesh corresponding to the image; initializing the anisotropic stiffness coefficient tensor based on residual point detection; constructing and solving a multi-scale mechanical equilibrium equation based on the minimum potential energy principle; calculating the difference between the current unpacked phase gradient and the prestress to obtain the local lattice strain field; dynamically updating the stiffness coefficients according to the strain magnitude based on a nonlinear plastic constitutive relation to simulate the plastic softening and fracture behavior in the shear region; iterating until the system potential energy converges, and outputting the target unpacked phase matrix. This invention accelerates convergence through multi-scale solving, suppresses noise and preserves phase discontinuity characteristics by utilizing anisotropic elastoplastic mechanisms, solves the problem of traditional algorithms easily producing stringing or excessive smoothing, and improves the accuracy of phase unpacking.

The application discloses a single-crystal single-pixel data acquisition and analysis method based on a neutron time-of-flight technology, and the method comprises the following steps: preliminarily orienting a single crystal to be measured; performing a TOF diffraction experiment on the single crystal to be measured, and rotating diffraction spots of a crystal face to be measured to a specified position of a detector according to the result of the preliminary orientation; screening target pixels according to single-pixel diffraction data on the detector, obtaining target pixel positions and diffraction spectra of the target pixels; performing fitting processing on the target pixels, obtaining a crystal face spacing of a specific diffraction crystal face of each pixel point, and a half-height width; calculating lattice strain of different target pixels, and drawing a crystal face spacing distribution diagram of a specific crystal face of the target pixels, a lattice strain distribution diagram, and a half-height width distribution diagram; and for a single-crystal high-temperature alloy, a misfit degree distribution diagram can also be drawn. The application can extract microstructure information of different regions in a diffraction volume of a single-crystal material, and has important significance for perfecting single-crystal material design, a preparation and production process, service damage evaluation and improving a service life of the material.

The invention provides a three-dimensional neutron diffraction orientation and strain field reconstruction method, system, medium and equipment, and the method comprises the steps: S1, according to a three-dimensional neutron diffraction technology principle, continuously rotating an Euler ring rotation angle to scan a material sample, and obtaining three-dimensional diffraction data; wherein the coordinates are detector coordinates and Euler ring rotation angles; s2, determining a two-dimensional rocking curve plane based on the three-dimensional diffraction data, discretizing the two-dimensional rocking curve plane to obtain a discretized angle unit, and taking the center of the angle unit as representative orientation; s3, obtaining a diffraction peak curve through in-plane integration for the discretized angle unit, fitting by using a pseudo Volight model to obtain a peak position parameter, calculating the interplanar spacing in the discrete unit based on the peak position parameter, and calculating the lattice strain in the discrete unit based on the interplanar spacing in the discrete unit; and S4, reconstructing a segmented constant orientation field and a strain field by taking all angle units as pixel grids.

The invention discloses an indium phosphide wafer substrate cleaning control method and system based on fluid pressure, and relates to the technical field of semiconductor material processing. The method comprises the following steps: acquiring reference lattice response rates, recovery rates and distortion reversible range thresholds in different crystal directions; measuring the fluid impact pressure and the lattice strain value of each area in real time in the cleaning process, and generating a real-time lattice response rate; the real-time lattice recovery rate is measured through intermittent voltage reduction; comparing the real-time rate with the reference rate to generate a response deviation and a recovery deviation, and identifying a lattice damage risk area according to the response deviation and the recovery deviation; the lattice strain value of the risk area is subjected to deviation correction and then is compared with a threshold value, the non-risk area is directly compared, and critical reversible pressure of each area is generated; and dynamic pressure regulation and control references facing different crystal orientations are output according to the critical pressure of each region. According to the invention, real-time monitoring and damage risk identification of the lattice state in the wafer cleaning process are realized, and an accurate reference is provided for differential pressure regulation and control.

This invention discloses a method and system for controlling the cleaning of indium phosphide wafer substrates based on fluid pressure, relating to the field of semiconductor material processing technology. The method includes: acquiring a reference lattice response rate, recovery rate, and distortion reversible range threshold for different crystal orientations; measuring the fluid impact pressure and lattice strain values ​​in each region in real time during the cleaning process to generate a real-time lattice response rate; intermittently reducing the pressure to measure the real-time lattice recovery rate; comparing the real-time rate with the reference rate to generate response deviation and recovery deviation, thereby identifying lattice damage risk areas; comparing the lattice strain values ​​of the risk areas with the threshold after deviation correction, and directly comparing the values ​​of non-risk areas to generate the critical reversible pressure for each region; and outputting a dynamic pressure control reference for different crystal orientations based on the critical pressure of each region. This invention achieves real-time monitoring of the lattice state and identification of damage risks during wafer cleaning, providing a precise reference for differentiated pressure control.

The invention provides a high-entropy alloy creep performance prediction method based on microstructure dynamic evolution, and belongs to the technical field of alloy material performance prediction. In order to solve the problems that an existing method excessively depends on an empirical formula, and macroscopic performance is separated from a micromechanism, a multi-physics field coupling dynamics calculation framework is constructed. The framework integrates dislocation dynamics, vacancy diffusion and a non-uniform lattice strain theory, and dynamic interaction and co-evolution of dislocation, vacancy and lattice strain are described in a self-consistent manner. Dislocation evolution, vacancy diffusion and interaction between the dislocation evolution, the vacancy diffusion and lattice strain are synchronously solved in each time step, and real-time bidirectional coupling of the dislocation evolution, the vacancy diffusion and the lattice strain is achieved. Experimental verification shows that the method can accurately predict the creep property of the high-entropy alloy and directly generate a creep strain-time curve. According to the method, microstructure evolution in the creep process can be quantified from intrinsic parameters and service conditions of materials, and an efficient theoretical tool and a calculation platform are provided for creep resistance design of the high-entropy alloy.

The invention relates to the technical field of power distribution network monitoring, and particularly discloses an intelligent monitoring method and device for a distribution network line fuse based on multi-parameter sensing, and the method comprises the steps: collecting the lattice strain of a fuse, the micro displacement of a contact, a harmonic frequency spectrum and a medium decomposition product, calculating a harmonic thermal equivalent coefficient, and carrying out the decoupling generation of a lattice intrinsic strain field, identifying a fretting wear phase point and a medium effective heat absorption rate; inputting the parameters into a multi-physical field degradation deduction model, and outputting a whisker critical bridging risk, contact resistance nonlinear jump probability distribution and a limit breaking capacity attenuation coefficient; and according to the risk value, calculating an actual protection capability boundary and generating a protection characteristic drift trajectory, performing space-time alignment on the drift trajectory of the multi-stage fuse, deducing a selective protection mismatch area and an evolution trend, and generating and issuing a reconstruction instruction including rated current adjustment, upper-stage delay correction or bypass protection starting. According to the invention, quantitative identification of the micro degradation process of the fuse and dynamic reconstruction of the protection capability are realized.

The invention discloses a method and a system for testing residual stress of a 4H-SiC ceramic-based composite material, strain information of the material in different crystal directions can be comprehensively captured by selecting a plurality of diffraction mirror azimuth angles psi and setting the direction of a Phi angle, contingency of single-point or single-direction measurement is avoided, measurement is carried out according to diffraction peak positions and azimuth angles, and the residual stress of the 4H-SiC ceramic-based composite material is obtained. The invention provides an accurate, reliable and reproducible residual stress test method, which ensures that a test result is derived from real lattice strain of a material instead of indirect or empirical estimation, so that the accuracy of the test result is remarkably improved, the final residual stress is calculated according to multidirectional results, and the repeatability and reliability of the measurement result are improved. The analysis period is short and the feasibility is high.

This silicon nitride sintered body is characterized in that the lattice strain of silicon nitride crystal grains constituting the silicon nitride sintered body is less than 0.003. According to the present invention, it is possible to provide a silicon nitride sintered body which is capable of forming a highly reliable silicon nitride circuit board having excellent temperature cycle characteristics.

The invention belongs to the technical field of semiconductors, and particularly relates to a hafnium compound, a precursor composition containing the hafnium compound, a thin film and a preparation method of the hafnium compound. The hafnium compound contains phosphorus and silicon and can be used as a precursor of a hafnium oxide film. The doping of phosphorus and silicon can effectively inhibit the growth of hafnium oxide grains at high temperature. And the hafnium is segregated at the grain boundary of hafnium oxide, so that the uniformity of the film is higher. Meanwhile, oxygen vacancy and lattice strain are introduced by doping phosphorus, so that the formation of a monoclinic phase with a low K value is inhibited, and the film can be kept at a relatively high K value; according to the present invention, the Si-O bond is connected with the Hf-O bond to form a mixed and randomly connected Si-O-Hf amorphous network, such that the energy barrier required by crystallization is improved so as to improve the thermal stability of the Si-O-Hf amorphous network;

The application provides a three-dimensional neutron diffraction data processing method and system of a single crystal material, comprising the following steps: performing rough scanning on a single crystal sample through a polar diagram mode to determine a rotation center of a single crystal sample signal; performing fine scanning at the rotation center to obtain a three-dimensional neutron diffraction signal; decomposing the three-dimensional neutron diffraction signal to obtain a diffraction peak curve and a rocking curve plane; correcting coordinates of the rocking curve plane; decomposing the corrected rocking curve plane to obtain a rocking curve; and quantitatively analyzing crystal face spacing and orientation distribution information in the three-dimensional diffraction signal according to the diffraction peak curve and the rocking curve. The application can non-destructively characterize the internal microstructure of the single crystal material, provides accurate data support for studying lattice strain distribution and orientation characteristics, and can further synchronously characterize and analyze the lattice spacing and orientation distribution information.

The invention relates to a preparation method of a phosphor-doped induced Ti4O7 lattice strain electrode and application of the phosphor-doped induced Ti4O7 lattice strain electrode in deep purification of electro-catalytic enhanced medical wastewater. PH3 generated in the in-situ P doping process is subjected to an oxidation-reduction reaction on the surface of Ti4O7 to form a new O vacancy, and meanwhile P is doped into a Ti-O-P structure in a Ti4O7 lattice. O vacancy is beneficial to improvement of conductivity of the system, Ti < 3 + > active sites can be increased, and generation of. OH is enhanced. A P site is constructed, and CO3 < 2-> adsorption and activation can be realized by utilizing an adjustable local electronic microenvironment, so that conversion of CO3 < 3-> into a CO3 < 3-> reaction energy barrier is reduced, and quenching of. OH by CO3 < 2-> is inhibited. Meanwhile, in the process of generating CO3 <.->, CO3 < 2-> transfers electrons to the surface of the electrode, and the electrons are effectively migrated to a Ti < 3 + > site through an O vacancy to inhibit the trend of conversion to a high valence state in the catalysis process, so that stable and efficient generation of. OH is realized, and antibiotics in the pharmaceutical wastewater are effectively degraded.

Provided are a fluorescent substance powder which has a high luminescent efficiency although being fine, and a method for producing the fluorescent substance powder. This fluorescent substance powder includes at least a Group-2 element (A), sulfur (S), and a luminescence center element (M), has a 90% volume-cumulative diameter (D90) of 10.0 μm or less, and has a lattice strain (σ), as determined by analyzing an X-ray diffraction profile by a WPPF method, of 0.300% or less.

The application provides a three-dimensional neutron diffraction orientation and strain field reconstruction method, system, medium and equipment, including: step S1: according to the principle of three-dimensional neutron diffraction technology, continuously rotating the Euler ring rotation angle to scan the material sample, and obtaining three-dimensional diffraction data; wherein, is the detector coordinate, and is the Euler ring rotation angle; step S2: based on the three-dimensional diffraction data, the two-dimensional rocking curve plane is determined, the two-dimensional rocking curve plane is discretized, the discretized angle unit is obtained, and the center of the angle unit is taken as the representative orientation; step S3: for the discretized angle unit, the diffraction peak curve is obtained by in-plane integration, and the peak position parameter is obtained by using the pseudo Voight model fitting, the crystal plane spacing in the discrete unit is calculated based on the peak position parameter, and the crystal lattice strain in the discrete unit is calculated based on the crystal plane spacing in the discrete unit; step S4: taking all angle units as a pixel grid, reconstructing the segmented constant orientation field and strain field.

The invention discloses a method for improving the stability of a wide bandgap perovskite solar cell by regulating and controlling lattice strain to inhibit ion migration. The method effectively solves the problem of phase segregation caused by lattice strain and ion migration in an optical active layer of the perovskite solar cell. In order to solve the problems of lattice strain and phase segregation generally existing in the perovskite thin film, the invention constructs an optimization strategy with residual strain relief and phase separation inhibition functions by introducing multifunctional molecules 1, 3-diaminopropane dihydroiodine (PDADI) on the optical active layer, thereby remarkably improving the crystal quality of the perovskite thin film prepared by a one-step solution method, and improving the performance of the perovskite thin film. And the comprehensive performance of the device is optimized.

Three-dimensional (3D) nanoarchitectured hexagonal boron nitride (hBN) is described with integrated solid-state single photon emitters (SPEs) from native defects generated during high-temperature chemical vapor deposition (CVD). The 3D hBN has a quasi-periodic gyroid minimal surface structure and is composed of a continuous 3D hBN sheet with built-in convex and concave curvatures that promote the formation of optically active and thermally robust native defects. The free-standing feature of the gyroid hBN with a nearly zero mean curvature can effectively eliminate the substrate disturbance and minimize lattice strain heterogeneity. As a result, naturally occurring defects with a narrow SPE spectral distribution can be created and activated as color centers in the 3D hBN, and the density of the SPEs can be tailored by CVD temperature.

The invention discloses a method for evaluating the period failure risk and the service life of a high-temperature alloy part by using HEXRD, which comprises the following steps: (1) setting a creep experiment in a synchrotron radiation device, applying constant stress and constant temperature to a high-temperature alloy part sample, starting HEXRD real-time monitoring at the same time, and collecting two-dimensional diffraction ring data at a preset sampling interval; and (2) software is used for processing data, the two-dimensional diffraction ring data is converted into a lattice strain and FWHM evolution curve along with time, peak splitting fitting is conducted on mixed peaks, a fitting result is obtained, and the high-temperature alloy can be Ni-based high-temperature alloy. According to the method, real-time and quantitative monitoring of the initial creep internal stress of the high-temperature alloy is achieved through the in-situ synchrotron radiation technology, the bottleneck that internal stress evolution cannot be dynamically tracked through a traditional method is solved, and direct technical support is provided for service safety evaluation.

The invention provides a 300mm large silicon wafer defect detection system based on synchrotron radiation light and a defect characterization method of the 300mm large silicon wafer defect detection system based on synchrotron radiation light, which can realize large-size and high-precision characterization based on a Bragg diffraction principle. Besides, the tested crystal is fixed on the rotary table and can rotate along a pitch angle under the driving of the rotary table, a series of two-dimensional diffraction images can be obtained in the rotation process of the tested crystal, and rocking curves of all pixels can be obtained through the series of two-dimensional diffraction images, so that local abrupt change and overall strain are separated. The large-size detected crystal can be spatially distinguished to achieve lattice strain of a pixel point level, the influence of external stress is separated, the interference of the clamping external stress of the detected crystal on the characterization of internal defects of the crystal is overcome, and the precision and the resolution of detecting the strain caused by the defects of the detected crystal are improved; and finally, by adopting the defect characterization method, the detection efficiency, the detection resolution and the detection precision can be effectively improved.

The present invention discloses a PHEMT device epitaxial structure and a preparation method thereof, belonging to the field of semiconductor technology. The structure comprises: an InP substrate, a GaAs buffer layer, an InGaAs pseudomorphic layer, an n-doped AlGaAs barrier layer, and a cap layer, which are sequentially stacked. The GaAs buffer layer and the n-doped AlGaAs barrier layer respectively form a first conductive channel and a second conductive channel in the InGaAs pseudomorphic layer for providing a 2DEG. The In component content of the InGaAs pseudomorphic layer is such that the sum of the lattice strain of the InGaAs pseudomorphic layer is less than the lattice mismatch stress of the heterojunction. Under the constraint of the In component content of the InGaAs pseudomorphic layer, the thickness of the InGaAs pseudomorphic layer is a target thickness such that the first conductive channel and the second conductive channel overlap, wherein the target thickness is used to enhance the concentration of the 2DEG, thereby improving device quality and performance.

The present invention discloses a method for non-destructively monitoring grain boundary relaxation strengthening of nanometals and a method for determining process parameters. The monitoring method comprises the following steps: (1) using an X-ray diffractometer to obtain diffraction patterns of at least two diffraction crystal planes during the nanometal grain boundary relaxation process; (2) calculating the interplanar spacing of each diffraction crystal plane during the nanometal grain boundary relaxation process; and (3) calculating the lattice strain of each diffraction crystal plane during the nanometal grain boundary relaxation process. The present invention proposes for the first time the use of X-ray diffraction technology to in-situ monitor the change in interplanar spacing during grain boundary relaxation (low-temperature heat treatment), using average lattice strain as a microstructural characteristic indicator that accurately reflects the degree of grain boundary relaxation. This effectively solves the problems of difficulty in determining heat treatment process parameters and ensuring the grain boundary relaxation strengthening effect, and provides process guidance and quality assurance for the preparation of high-performance nanometal materials using high-efficiency, low-energy heat treatment designs.