2166results about "Eutectic material solidification" patented technology

A method for producing a nitride semiconductor, comprising controlling temperature and pressure in a autoclave containing a seed having a hexagonal crystal structure, a nitrogen element-containing solvent, a raw material substance containing a metal element of Group 13 of the Periodic Table, and a mineralizer so as to put said solvent into a supercritical state and/or a subcritical state and thereby ammonothermally grow a nitride semiconductor crystal on the surface of said seed, wherein the crystal growth rate in the m-axis direction on said seed is 1.5 times or more the crystal growth rate in the c-axis direction on said seed. By the method, a nitride semiconductor having a large-diameter C plane or a nitride semiconductor thick in the m-axis direction can be efficiently and simply produced.

A method for large-scale manufacturing of gallium nitride boules. Large-area single crystal seed plates are suspended in a rack, placed in a large diameter autoclave or internally-heated high pressure apparatus along with ammonia and a mineralizer, and grown ammonothermally. The seed orientation and mounting geometry are chosen to provide efficient utilization of the seed plates and of the volume inside the autoclave or high pressure apparatus. The method is scalable up to very large volumes and is cost effective.

The present invention provides a method of forming a strained semiconductor layer. The method comprises growing a strained first semiconductor layer, having a graded dopant profile, on a wafer, having a first lattice constant. The dopant imparts a second lattice constant to the first semiconductor layer. The method further comprises growing a strained boxed second semiconductor layer having the second lattice constant on the first semiconductor layer and growing a sacrificial third semiconductor layer having the first lattice constant on the second semiconductor layer. The method further comprises etch annealing the third and second semiconductor layer, wherein the third semiconductor layer is removed and the second semiconductor layer is relaxed. The method may further comprises growing a fourth semiconductor layer having the second lattice constant on the second semiconductor layer, wherein the fourth semiconductor layer is relaxed, and growing a strained fifth semiconductor layer having the first semiconductor lattice constant on the fourth semiconductor layer. The method controls the surface roughness of the semiconductor layers. The method also has the unexpected benefit of reducing dislocations in the semiconductor layers.

A high pressure apparatus and related methods for processing supercritical fluids. In a specific embodiment, the present apparatus includes a capsule, a heater, at least one ceramic ring but can be multiple rings, optionally, with one or more scribe marks and/or cracks present. In a specific embodiment, the apparatus optionally has a metal sleeve containing each ceramic ring. The apparatus also has a high-strength enclosure, end flanges with associated insulation, and a power control system. In a specific embodiment, the apparatus is capable of accessing pressures and temperatures of 0.2-2 GPa and 400-1200° C., respectively.

The present invention provides microfabricated substrates and methods of conducting reactions within these substrates. The reactions occur in plugs transported in the flow of a carrier-fluid.

A method of synthesizing colloidal nanocrystals is disclosed using metal oxides or metal salts as a precursor. The metal oxides or metal salts are combined with a ligand and then heated in combination with a coordinating solvent. Upon heating, the metal oxides or salts are converted to stable soluble metal complexes. The metal complexes are formed by cationic species combining with the ligands and/or with the coordinating solvent. Finally, an elemental chalcogenic precursor, for example, Se, Te, or S, is introduced into the soluble metal complex to complete the formation of the nanocrystals at a controllable rate. High-quality CdSe, CdTe, and CdS nanocrystals are produced when CdO is used as the cadmium precursor. With the present method, the size, size distribution, and shape (dots or rods) of the resulting nanocrystals can be controlled during growth. For example, the resulting nanocrystals are nearly monodisperse without any size separation. Further, the method represents a major step towards a green chemistry approach for synthesizing high-quality semiconductor nanocrystals.

A method of manufacturing a single crystal ingot, and a single crystal ingot and a wafer manufactured thereby are provided. The method of manufacturing a single crystal ingot according to an embodiment includes forming a silicon melt in a crucible inside a chamber, preparing a seed crystal on the silicon melt, and growing a single crystal ingot from the silicon melt, and pressure of the chamber may be controlled in a range of 90 Torr to 500 Torr.

Methods and systems for depositing nanomaterials onto a receiving substrate and optionally for depositing those materials in a desired orientation, that comprise providing nanomaterials on a transfer substrate and contacting the nanomaterials with an adherent material disposed upon a surface or portions of a surface of a receiving substrate. Orientation is optionally provided by moving the transfer and receiving substrates relative to each other during the transfer process.

A pressure vessel for processing at least one material in a supercritical fluid. The pressure vessel includes a self-pressurizing capsule for containing at least one material and the supercritical fluid in a substantially air-free environment, a pressure transmission medium surrounding the capsule for maintaining an outer pressure on the capsule, at least one heating element insertable in the pressure transmission medium such that the heating element surrounds the capsule, a temperature measurement means for measuring a temperature of the capsule, a temperature controller for controlling the temperature and providing power to the heating element, a restraint to contain and hold in place the capsule, the pressure transmission medium, and the heating element, and at least one seal between the restraint and the pressure transmission medium for preventing escape of the pressure transmission medium. Methods of using the pressure vessel, processing a material at high temperature and high pressure in the presence of a supercritical fluid within the capsule are also described.

The invention is related to nuclear physics, medicine and oil industry, namely to the measurement of x-ray, gamma and alpha radiation; control for trans uranium nuclides in the habitat of a man; non destructive control for the structure of heavy bodies; three dimensional positron-electron computer tomography, etc.The essence of the invention is in additional ingredients in a chemical composition of a scintillating material based on crystals of oxyorthosilicates, including cerium Ce and crystallized in a structural type Lu2SiO5.The result of the invention is the increase of the light output of the luminescence, decrease of the time of luminescence of the ions Ce3+, increase of the reproducibility of grown crystals properties, decrease of the cost of the source melting stock for growing scintillator crystals, containing a large amount of Lu2O3, the raise of the effectiveness of the introduction of SCintillating crystal luminescent radiation into a glass waveguide fibre, prevention of cracking of crystals during the production of elements, creation of waveguide properties in scintillating elements, exclusion of expensive mechanical polishing of their lateral surface.

The present invention is related to a process for obtaining a larger area substrate of mono-crystalline gallium-containing nitride by making selective crystallization of gallium containing nitride on a smaller seed under a crystallization temperature and/or pressure from a supercritical ammonia-containing solution made by dissolution of gallium-containing feedstock in a supercritical ammonia-containing solvent with alkali metal ions, comprising: providing two or more elementary seeds, and making selective crystallization on the two or more separate elementary seeds to get a merged larger compound seed. The merged larger compound seed is used for a seed in a new growth process and then to get a larger substrate of mono-crystal gallium-containing nitride.

Apparatus and methods are described for fabricating a compound nitride semiconductor structure. Group-III and nitrogen precursors are flowed into a first processing chamber to deposit a first layer over a substrate with a thermal chemical-vapor-deposition process. The substrate is transferred from the first processing chamber to a second processing chamber. Group-III and nitrogen precursors are flowed into the second processing chamber to deposit a second layer over the first layer with a thermal chemical-vapor-deposition process. The first and second group-III precursors have different group-III elements.

High throughput screening of crystallization of a target material is accomplished by simultaneously introducing a solution of the target material into a plurality of chambers of a microfabricated fluidic device. The microfabricated fluidic device is then manipulated to vary the solution condition in the chambers, thereby simultaneously providing a large number of crystallization environments. Control over changed solution conditions may result from a variety of techniques, including but not limited to metering volumes of crystallizing agent into the chamber by volume exclusion, by entrapment of volumes of crystallizing agent determined by the dimensions of the microfabricated structure, or by cross-channel injection of sample and crystallizing agent into an array of junctions defined by intersecting orthogonal flow channels.

A method for large-scale manufacturing of gallium nitride includes a process for reducing and/or minimizing contamination in the crystals, for solvent addition to an autoclave, for improving or optimizing the solvent atmosphere composition, for removal of the solvent from the autoclave, and for recycling of the solvent. The method is scalable up to large volumes and is cost effective.

An apparatus for growing a biological macromolecular crystal by vaporizing biological macromolecular solution into an oversaturated state. The apparatus includes a first sealed room that receives first crystallizing agent solution, and a communicating tube that communicates with the first sealed room and has a small sectional area for suppressing convection of air. A plurality of droplets of solution dissolving a biological macromolecule and a crystallizing agent therein are held in the communicating tube with the plurality of droplets being separated from each other.