47 results about "Wurtzite crystal structure" patented technology

Optoelectronic devices, such as light-emitting diodes, laser diodes, image sensors, optical detectors, etc., made by depositing (growing) one or more epitaxial semiconductor layers on a monocrystalline lamellar/layered substrate so that each layer has a wurtzite crystal structure. In some embodiments, the layers are deposited and then one or more lamellas of the starting substrate are removed from the rest of the substrate. In one subset of such embodiments, the removed lamella(s) is/are partially or entirely removed. In other embodiments, one or more lamellas of the starting substrate are removed prior to depositing the one or more wurtzite-crystal-structure-containing layer(s).

In a plated steel sheet having an aluminum-plating layer comprising at least Al formed on one side or both sides of the steel sheet, there is provided a plated steel sheet which, owing to the presence of a surface coating layer containing a compound having wurtzite crystal structure on the aluminum-plating layer, has excellent lubricity, prevents the plating thickness from becoming uneven during heating, and can improve formability and productivity in hot stamping, and a method of hot-stamping the plated steel sheet.

A substrate for an electronic device comprises a base, an adhesion film stacked on the base, and a conductor film stacked on the adhesion film. The adhesion film is a non-epitaxial film including a crystal having a wurtzite crystal structure. The electronic device comprises the substrate and a functional film having a specific function and disposed on the substrate.

The invention discloses a one-dimensional cadmium sulfide nanorod catalyst, and a preparation method thereof and an application thereof in producing hydrogen through acoustic catalytic cracking of water. The catalyst has a wurtzite crystal structure, and is non-centrosymmetric crystal. The catalyst satisfy the structural condition of piezoelectric crystal. The specially oriented nanorod shape of the catalyst can enrich environmental soundwave energy through piezoelectric effect, such that negative charge is produced on the surface of the nanorods. Therefore, pure water cracking is catalyzed, and hydrogen gas is produced. The preparation method mainly relates to a one-step solvothermal method. Cadmium sulfide growth orientation is regulated with the coordination or chelation effect of crystal seeds and diethylenetriamine solvent molecules, and the one-dimensional nanorod morphology is obtained under appropriate reaction temperature and reaction time conditions. The activity of the obtained cadmium sulfide nanorods for cracking pure water to produce hydrogen under sound driving is substantially higher than those of nano-flake wurtzite-type cadmium sulfide sample, micro-spherical wurtzite-type cadmium sulfide sample, and nanorod wurtzite-type cadmium sulfide samples obtained with a traditional two-step synthesis method. The cadmium sulfide nanorod catalyst provided by the invention has a good application prospect in the field of sound energy-hydrogen energy conversion. The preparation method is simple to operate, and is suitable for industrialized production.

The invention relates to a method of preparing a nitride epitaxial layer, a substrate and a device wafer. The method comprises the steps of using at least one oxide film in a wurtzite-like crystal structure as a sacrificial layer to connect with the nitride epitaxial layer and the initial substrate; meanwhile, realizing the separation between the nitride epitaxial layer and the initial substrate through a chemical stripping method. According to the method provided by the invention, a selected oxide is likely to be decomposed in a chemical solution to realize wet etching, therefore, the beneficial conditions are provided for substrate stripping, substrate transferring, wafer bonding and other process technologies in the process of preparing the nitride epitaxial layer, a nitride substrate or a nitride device wafer, and the higher crystal quality of a material of the nitride epitaxial layer can be ensured.

The optical semiconductor of the present invention is an optical semiconductor containing In, Ga, Zn, O and N, and has a composition in which a part of oxygen (O) is substituted by nitrogen (N) in a general formula: In_2xGa_2(1-x)O₃(ZnO)_y, where x and y satisfy 0.2<x<1 and 0.5≦y. In the general formula, x is preferably 0.5, and furthermore, y is preferably 1 or more and 6 or less, and more preferably 2 or 6. It is preferred that the optical semiconductor of the present invention have a wurtzite crystal structure. The optical semiconductor of the present invention is an excellent optical semiconductor because it has a smaller band gap, can utilize visible light, and has high carrier mobility and thus has high quantum efficiency.

The invention provides an aluminum nitride nanometer comb and a preparation method thereof, belonging to the technical field of a nanometer material and preparation thereof. The aluminum nitride nanometer comb is a nanometer comb with a bilateral comb-shaped structure formed by a nanometer wire array, or a mixed structure of the bilateral comb-shaped structure and a monolateral comb-shaped structure, wherein the nanometer wire is formed by AlN with a hexagonal wurtzite crystal structure, with diameter of about between 50 and 80 nanometers and length of about between 1 and 1.5mu meters. The preparation method adopts a direct-current electrical arc discharge device, and leads metal aluminum to react with a mixed gas of nitrogen and ammonia under a condition of high-temperature and low pressure system so as to prepare a white nanometer comb sample. The method synthesizes the AlN nanometer comb structure with high purity and even arrangement for the first time; the preparation method has the advantages of simpleness, good repeatability, short time, low cost and friendly to environment; and the comb and the method have application prospect in laser interference/coupling, nanometer laser array, nanometer electro-mechanics and other fields.

A magnetic recording medium is provided, which has at least one soft magnetic layer, at least one seed layer, at least one underlayer and at least one perpendicular magnetic recording layer, and is characterized in that the or each seed layer is comprised of a covalently bonded material. The covalently bonded material preferably predominantly comprises a nitride having a hexagonal crystal structure, more preferably, predominantly comprises aluminum nitride having a hexagonal wurtzite crystal structure. This magnetic recording medium is superior in recording and reproducing an information with high density.

A semiconductor substrate (1) of the present invention is made of nitrides of group III metals having wurtzite crystal structure and is grown in vapor phase either on a (0001) oriented foreign substrate (2), lattice mismatched to the semiconductor substrate materials, or on existing (0001) oriented highly dislocated layer (3) of the semiconductor substrate materials and has a highly reduced dislocation density. According to the present invention, a structure is utilized for the dislocation density reduction, which comprises a dislocation redirection layer (4) providing intentional inclination of threading dislocations (6) towards high index crystallographic planes having crystallographic indexes other than (0001) and those of the type {1 100}, in order to enhance the probability for dislocation reactions; and a dislocation reaction layer (5) positioned above said dislocation layer (4), in which the threading dislocations (6) coalesce with each other resulting in reduced threading dislocation density at the semiconductor substrate surface (7).

The invention provides a method for preparing nano zinc oxide. The method specifically comprises the following steps of: ultrasonically dispersing zinc powder into pure water contained in a liner of a reaction kettle; sealing the reaction kettle, and then preserving the heat of the reaction kettle for 18-72 hours in a drying oven of which the temperature is 180-200 DEG C; cooling to the room temperature; filtering out the material in the liner, and performing vacuum drying on the material to obtain a product. The product is the nano zinc oxide with a wurzite hexagonal crystal structure, and can be widely used in a plurality of fields including photocatalysis, photovoltaic conversion, sensing detection, optics, microelectronics and the like. The preparation method provided by the invention has the characteristics of zero pollution, low cost, simple process, convenient operation, easiness in industrial production and the like.

The invention relates to an aluminum nitride unilateral nano comb and a preparation method thereof, and belongs to the technical field of nano materials and preparation of the nano materials. The aluminum nitride unilateral nano comb has a unilateral pectinate structure formed by a nano wire array, wherein a nano wire is grown from one side of a middle stem and consists of AIN with a hexagonal wurtzite crystal structure; and the diameter of the nano wire is approximately between 50 and 80 nanometers in general, and the length of the nano wire is approximately between 1 and 1.5 mu m. The preparation method adopts a direct-current arc discharge device, makes metallic aluminum directly react with mixed gas of nitrogen and ammonia gas under the condition of a high-temperature and low-pressure system, and prepares a white nano comb sample. The method synthesizes the AIN unilateral nano comb structure with high purity and uniform arrangement for the first time; the preparation method is simple and environment-friendly, and has good repeatability, short time, and low cost; and the aluminum nitride unilateral nano comb has application prospect in the aspects of laser interference/coupling, nano laser arrays, nano electromechanical systems, and the like.

The invention particularly relates to a cadmium sulfide nanorod and a method for friction catalytic degradation of organic pollutants. The cadmium sulfide nanorod is of a hexagonal wurtzite crystal structure, belongs to a non-centrosymmetric point group, and has a specific diameter of 40-50 nm and a length-diameter ratio of 8: 1 to 100: 1. According to the cadmium sulfide nanorod and the method for friction catalytic degradation of organic pollutants in the invention, operation is simple; the piezoelectric property of cadmium sulfide with a specific structure is utilized, so mechanical energyin an environment can be enriched more effectively; organic matter degradation can be achieved only through magnetic stirring under a dark condition, so the problem that a conventional photocatalysisexperiment is low in visible light response efficiency is solved; and meanwhile, the demand for equipment capable of generating sound waves in piezoelectric catalysis is avoided, sewage degradation efficiency is greatly improved, sewage treatment cost is reduced, and the method is suitable for application and popularization.

A semiconductor structure is formed of nitrides of group III metals having wurtzite crystal structure and grown in vapor phase on a (0001) oriented semiconductor substrate. The structure comprises a bottom cladding layer, a top cladding layer, and a diffusion region positioned between the cladding layers for diffusing light propagating within the semiconductor structure. The diffuse region has refractive index different from those of the cladding layers and non-flat surfaces for providing light diffusing interfaces between the diffusion region and the cladding layers. According to the invention, the diffusion region comprises a plurality of diffusion layers, compositions and thicknesses of said diffusion layers having been chosen to avoid formation of strain-induced dislocations in the diffusion region, and adjacent diffusion layers having different refractive indices in order to further enhance the diffusion efficiency.

A group III nitride semiconductor light emitting diode is revealed. A layered structure composed of group III nitrides is formed on the substrate through epitaxy growth of a hexagonal wurtzite crystal structure. The layered structure includes a n-type semiconductor layer, a light emitting layer on the n-type semiconductor layer, and a p-type semiconductor layer on the light emitting layer. A first electrode metal pad is formed on the p-type semiconductor layer and a second electrode metal pad on the n-type semiconductor layer. A direction from the first electrode metal pad to the second electrode metal pad is the same with that of C-axis [0001] of the hexagonal wurtzite crystal structure so as to speed up the movement of electron-hole and improve the combination efficiency of electron-hole by the electric field along the direction of C-axis [0001] in the hexagonal wurtzite crystal structure.

A nitride semiconductor epitaxial wafer includes a substrate, a GaN layer provided over the substrate, and an AlGaN layer provided over the GaN layer. The GaN layer has a wurtzite crystal structure, and a ratio c/a of a lattice constant c in a c-axis orientation of the GaN layer to a lattice constant a in an a-axis orientation of the GaN layer is not more than 1.6266.

The invention relates to a field emission cathode with an electron emission-enhanced mixed phase nitride film and a preparation method for the field emission cathode, and belongs to the technical field of field emission cathodes. The cathode is made of a mixture of GaN and AlN, has a hexagonal wurtzite crystal structure and a cubic sphalerite crystal structure, and comprises the component of AlxGa1-xN, wherein x is more than 0 and is less than or equal to 0.95. The preparation method comprises the following steps of: putting a substrate and a target material formed by sintering the GaN and the AlN into a laser pulse deposit system, vacuumizing, heating the substrate, introducing protective gas, and preparing a nanometer film with an aluminum gallium nitride wurtzite hexagonal phase and a sphalerite cubic phase which coexist by using the laser pulse deposit system. Compared with a single-phase film, the nanometer film has the advantage that: the field emission cut-in voltage and the maximum current density are improved by 2 to 5 orders of magnitude. By the nanometer film with the two phases which coexist, the improvement on the field emission performance of the film and the commercialization of a field emission display is facilitated, so the field emission cathode has an obvious application prospect and a potential economic benefit.

The invention provides a C-axle preferred orientation single-crystal ZnO hexagonus microtube preparation method. C-axle preferred orientation single-crystal ZnO hexagonus microtube is prepared from predecessor through hydrothermal synthesis, the said predecessor being zinc salt or zincate, including zinc acetate or zinc acetate group chemical etc. ZnO microtube prepared in the invention is single crystal microtube, and has identical complete hexagonus structure with crystal structure of hexagonal faserblende which is ZnO single crystal, C-axle of which is axially oriented along the tube. Hydrothermal synthesis method in the invention has advantages of simple process, good product uniformity and repeatability ,predecessor being easily synthesized.