Abstract: A method for minimizing unwanted ancillary reactions in a vacuum furnace used to process a material, such as growing a crystal. The process is conducted in a furnace chamber environment in which helium is admitted to the furnace chamber at a flow rate to flush out impurities and at a predetermined pressure to achieve thermal stability in a heat zone, to minimize heat flow variations and to minimize temperature gradients in the heat zone. During cooldown helium pressure is used to reduce thermal gradients in order to increase cooldown rates.

Abstract: The invention relates to the technology for producing three-dimensional monocrystals and can preferably be used in optoelectronics for manufacturing substrates for various optoelectronic devices, including light-emitting diodes that emit light in the ultraviolet region. The method for growing an AlN monocrystal by gas-phase epitaxy from a mixture containing a source of Al and NH3 comprises arranging the Al source and a substrate, with the growth surface of said substrate turned towards said Al source, opposite one another in a growth chamber, said source and substrate forming a growth zone, producing a flow of NH3 in the growth zone; and heating the Al source and the substrate to temperatures that ensure the growth of the AlN monocrystal on the substrate. The Al source used is only free Al, the substrate is pretreated with Ga and/or In, whereupon the Al source is cooled to a temperature of 800-900° C. and the substrate is annealed by being heated to a temperature of 1300-1400° C.

Abstract: Process for producing silicon oxide containing thin films on a growth substrate by the ALCVD method. In the process, a vaporisable silicon compound is bonded to the growth substrate, and the bonded silicon compound is converted to silicon dioxide. The invention comprises using a silicon compound which contains at least one organic ligand and the bonded silicon compound is converted to silicon dioxide by contacting it with a vaporised, reactive oxygen source, in particular with ozone. The present invention provides a controlled process for growing controlling thin films containing SiO2, with sufficiently short reaction times.

Abstract: A system for growing a crystal ingot from a melt is provided. The system includes a first crucible, a barrier, and a shield. The first crucible has a first base and a first sidewall forming a first cavity for containing the melt. The barrier is disposed within the first cavity of the first crucible to inhibit movement of the melt from outward of the barrier to inward of the barrier. The barrier extends from the first base to above the melt. The barrier has an inner arm and an outer arm extending upward to form a channel therebetween. The shield extends downward between the inner arm and the outer arm to inhibit passage of contaminants.

Abstract: A base for making an epitaxial structure is provided. The base includes a substrate and a carbon nanotube layer. The substrate has an epitaxial growth surface. The carbon nanotube layer is located on the epitaxial growth surface. The carbon nanotube layer defines a plurality of apertures to expose part of the epitaxial growth surface so that an epitaxial layer can grow from an exposed epitaxial growth surface and through the apertures. A method for making an epitaxial structure using the base is also provided.

Abstract: A process for producing a doped III-N bulk crystal, wherein III denotes at least one element of the main group III of the periodic system, selected from Al, Ga and In, wherein the doped crystalline III-N layer or the doped III-N bulk crystal is deposited on a substrate or template in a reactor, and wherein the feeding of at least one dopant into the reactor is carried out in admixture with at least one group III material. In this manner, III-N bulk crystals and III-N single crystal substrates separated therefrom can be obtained with a very homogeneous distribution of dopants in the growth direction as well as in the growth plane perpendicular thereto, a very homogeneous distribution of charge carriers and/or of the specific electric resistivity in the growth direction as well as in the growth plane perpendicular thereto, and a very good crystal quality.

Abstract: In various embodiments, methods of forming single-crystal AlN include providing a substantially undoped polycrystalline AlN ceramic having an oxygen concentration less than approximately 100 ppm, forming a single-crystal bulk AlN crystal by a sublimation-recondensation process at a temperature greater than approximately 2000° C., and cooling the bulk AlN crystal to a first temperature between approximately 1500° C. and approximately 1800° C. at a first rate less than approximately 250° C./hour.

Abstract: The object is to provide a photoelectric surface member which allows higher quantum efficiency. In order to achieve this object, a photoelectric surface member 1a is a crystalline layer formed by a nitride type semiconductor material, and comprises a nitride semiconductor crystal layer 10 where the direction from the first surface 101 to the second surface 102 is the negative c polar direction of the crystal, an adhesive layer 12 formed along the first surface 101 of the nitride semiconductor crystal layer 10, and a glass substrate 14 which is adhesively fixed to the adhesive layer 12 such that the adhesive layer 12 is located between the glass substrate 14 and the nitride semiconductor crystal layer 10.

Abstract: Provided is a vitreous silica crucible having a reference point, which is capable of accurately detecting the location of a defect in the vitreous silica crucible used for pulling silicon single crystal, determining a defect generating site of silicon single crystal, and investigating the cause of the defect. The reference point used for specifying the position relationship with respect to a particular part is formed in at least one site of an end portion, an inner wall and an outer wall of the crucible.

Abstract: Apparatus and methods for controlling gas flows in a HVPE reactor. Gas flows may be controlled by a gas focusing element. Gas injection and gas collection tubes are positioned within an outer tube and are separated from each other to define a space there between. A gas, such as HCl gas, flows over the outer surfaces of the injection and collection tubes to contain gases within the space as they flow from the injection tube to the collection tube and over a seed upon which group III nitride materials are grown. Gas flows may also be controlled by a multi-tube structure that separates gases until they reach a grown zone. A multi-tube structure may include four tubes, which separate flows of a halide reactive gas, a reaction product that flows with a carrier gas, and ammonia.

Abstract: A method of manufacturing a group 13 nitride crystal includes a crystal growth process to form the group 13 nitride crystal by growing the group 13 nitride crystal having a hexagonal crystal structure from a seed crystal which is a gallium nitride crystal having a hexagonal crystal structure in which a length “L” in a c-axis direction is 9.7 mm or more, and a ratio L/d of the length “L” to a crystal diameter “d” in a c-plane is larger than 0.813. The crystal growth process includes a process of forming an outer periphery containing a {10-10} plane and an outer periphery containing a {10-11} plane at side surfaces of the group 13 nitride crystal, and forming an outer periphery containing a {0001} plane at a bottom surface of the group 13 nitride crystal.

Abstract: The present invention is directed to a single-crystal silicon pulling silica container, the silica container including a straight body portion, a curved portion, and a bottom portion, wherein the OH group concentration in the straight body portion is 30 to 300 ppm by mass, the OH group concentration in the bottom portion is 30 ppm by mass or less, and the difference in the OH group concentration between the straight body portion and the bottom portion is 30 ppm by mass or more. As a result, a low-cost single-crystal silicon pulling silica container, the silica container that can reduce cavity defects called voids and pinholes in pulled single crystal silicon, is provided.

Abstract: A method of manufacturing an epitaxial wafer, including a silicon substrate having a surface sliced from single-crystalline silicon and a silicon epitaxial layer deposited on the surface of the silicon substrate, includes an oxygen concentration controlling heat treatment process in which a heat treatment of the epitaxial layer is performed under a non-oxidizing atmosphere after the epitaxial growth such that an oxygen concentration of the surface of the silicon epitaxial layer is set to 1.0×1017 to 12×1017 atoms/cm3 (ASTM F-121, 1979).

Abstract: Provided is a method for manufacturing a silicon carbide single crystal using a solution process including coming a seed crystal substrate for growing silicon carbide into contact with a Si—C alloy solution including at least one additive metal and growing the silicon carbide single crystal on a seed crystal for growing silicon carbide, including feeding a silicon feedstock into an alloy solution when a molar ratio of Si and the additive metal is lower than an initially set value as the reaction progresses. The method increases a crystal growth speed, maintains the growth speed, and prevents the growth from unwillingly stopping when the silicon carbide single crystal is manufactured using a solution growth process.

Abstract: The present invention relates to an apparatus and method for purifying materials using a rapid directional solidification. Devices and methods shown provide control over a temperature gradient and cooling rate during directional solidification, which results in a material of higher purity. The apparatus and methods of the present invention can be used to make silicon material for use in solar applications such as solar cells.

Abstract: A method of producing an epitaxial wafer, comprising: performing epitaxial growth of silicon on a main surface of a wafer made of a silicon single crystal; performing surface flattening pretreatment of a main surface of the wafer using a treatment liquid of a predetermined composition at a temperature of 100° C. or less, thereby forming an oxide film of a predetermined thickness while removing particles adhered on the main surface of the wafer; and performing a surface polishing step where the main surface of the wafer is mirror polished.

Abstract: The present invention provides a method for preparing a thin or thick film, comprising the steps of: (1) arranging non-spherical seed crystals on a substrate such that all the a-, b- and c-axes of each seed crystal are oriented under a predetermined rule; and (2) forming and growing the film from the seed crystals through secondary growth by exposing the arranged seed crystals of step (1) to a seed crystal growth solution. The invention also provides a film prepared by the method. According to the invention, crystals or films larger than the seed crystals can be prepared.

Abstract: Heterogeneous nanowires having a core-shell structure consisting of single-crystal apatite as the core and graphitic layers as the shell and a synthesis method thereof are provided. More specifically, provided is a method capable of producing large amounts of heterogeneous nanowires, composed of graphitic shells and apatite cores, in a reproducible manner, by preparing a substrate including an element corresponding to X of X5(YO4)3Z is a chemical formula for apatite, adding to the substrate a gaseous source containing an element corresponding to Y of the chemical formula, adding thereto a gaseous carbon source, and allowing these reactants to react under optimized synthesis conditions using chemical vapor deposition (CVD), and to a method capable of freely controlling the structure and size of the heterogeneous nanowires and also to heterogeneous nanowires synthesized thereby.

Abstract: A group III element nitride single crystal is grown on a template immersed in a raw material liquid retained in a crucible and containing a group III material and one of an alkali metal and an alkali earth metal. The raw material liquid remaining after the growth of the single crystal is cooled and solidified, and by feeding a hydroxyl group-containing solution into the crucible, the solidified raw material is removed from around the template, and thus the group III element nitride single crystal is taken out from inside the solidified raw material. The template is disposed at a position away from the bottom of the crucible.

Abstract: Epitaxially coated semiconductor wafers are prepared by a process in which a semiconductor wafer polished at least on its front side is placed on a susceptor in a single-wafer epitaxy reactor and epitaxially coated on its polished front side at temperatures of 1000-1200° C., wherein, after coating, the semiconductor wafer is cooled in the temperature range from 1200° C. to 900° C. at a rate of less than 5° C. per second. In a second method for producing an epitaxially coated wafer, the wafer is placed on a susceptor in the epitaxy reactor and epitaxially coated on its polished front side at a deposition temperature of 1000-1200° C., and after coating, and while still at the deposition temperature, the wafer is raised for 1-60 seconds to break connections between susceptor and wafer produced by deposited semiconductor material before the wafer is cooled.