Patent classifications
C30B19/12
Methods of producing seed crystal substrates and group 13 element nitride crystals, and seed crystal substrates
A seed crystal layer is provided on a supporting body. A laser light is irradiated from a side of the supporting body to provide an altered portion along an interface between the supporting body and seed crystal layer. The altered layer is composed of a nitride of a group 13 element and has a portion into which dislocation defects are introduced or an amorphous portion.
Methods of producing seed crystal substrates and group 13 element nitride crystals, and seed crystal substrates
A seed crystal layer is provided on a supporting body. A laser light is irradiated from a side of the supporting body to provide an altered portion along an interface between the supporting body and seed crystal layer. The altered layer is composed of a nitride of a group 13 element and has a portion into which dislocation defects are introduced or an amorphous portion.
Seed wafer for GaN thickening using gas- or liquid-phase epitaxy
Embodiments relate to fabricating a wafer including a thin, high-quality single crystal GaN layer serving as a template for formation of additional GaN material. A bulk ingot of GaN material is subjected to implantation to form a subsurface cleave region. The implanted bulk material is bonded to a substrate having lattice and/or Coefficient of Thermal Expansion (CTE) properties compatible with GaN. Examples of such substrate materials can include but are not limited to AlN and Mullite. The GaN seed layer is transferred by a controlled cleaving process from the implanted bulk material to the substrate surface. The resulting combination of the substrate and the GaN seed layer, can form a template for subsequent growth of overlying high quality GaN. Growth of high-quality GaN can take place utilizing techniques such as Liquid Phase Epitaxy (LPE) or gas phase epitaxy, e.g., Metallo-Organic Chemical Vapor Deposition (MOCVD) or Hydride Vapor Phase Epitaxy (HVPE).
Seed wafer for GaN thickening using gas- or liquid-phase epitaxy
Embodiments relate to fabricating a wafer including a thin, high-quality single crystal GaN layer serving as a template for formation of additional GaN material. A bulk ingot of GaN material is subjected to implantation to form a subsurface cleave region. The implanted bulk material is bonded to a substrate having lattice and/or Coefficient of Thermal Expansion (CTE) properties compatible with GaN. Examples of such substrate materials can include but are not limited to AlN and Mullite. The GaN seed layer is transferred by a controlled cleaving process from the implanted bulk material to the substrate surface. The resulting combination of the substrate and the GaN seed layer, can form a template for subsequent growth of overlying high quality GaN. Growth of high-quality GaN can take place utilizing techniques such as Liquid Phase Epitaxy (LPE) or gas phase epitaxy, e.g., Metallo-Organic Chemical Vapor Deposition (MOCVD) or Hydride Vapor Phase Epitaxy (HVPE).
Single-Crystal Perovskite Solid Solutions With Indifferent Points for Epitaxial Growth of Single Crystals
Growth of single crystal epitaxial films of the perovskite crystal structure by liquid- or vapor-phase means can be accomplished by providing single-crystal perovskite substrate materials of improved lattice parameter match in the lattice parameter range of interest. Current substrates do not provide as good a lattice match, have inferior properties, or are of limited size and availability because cost of materials and difficulty of growth. This problem is solved by the single-crystal perovskite solid solutions described herein grown from mixtures with an indifferent melting point that occurs at a congruently melting composition at a temperature minimum in the melting curve in the pseudo-binary molar phase diagram. Accordingly, single-crystal perovskite solid solutions, structures, and devices including single-crystal perovskite solid solutions, and methods of making single-crystal perovskite solid solutions are described herein.
Single-Crystal Perovskite Solid Solutions With Indifferent Points for Epitaxial Growth of Single Crystals
Growth of single crystal epitaxial films of the perovskite crystal structure by liquid- or vapor-phase means can be accomplished by providing single-crystal perovskite substrate materials of improved lattice parameter match in the lattice parameter range of interest. Current substrates do not provide as good a lattice match, have inferior properties, or are of limited size and availability because cost of materials and difficulty of growth. This problem is solved by the single-crystal perovskite solid solutions described herein grown from mixtures with an indifferent melting point that occurs at a congruently melting composition at a temperature minimum in the melting curve in the pseudo-binary molar phase diagram. Accordingly, single-crystal perovskite solid solutions, structures, and devices including single-crystal perovskite solid solutions, and methods of making single-crystal perovskite solid solutions are described herein.
N-type SiC single crystal and method for its production
A n-type SiC single crystal with low resistivity and low threading dislocation density is provided, which is achieved by a n-type SiC single crystal containing germanium and nitrogen, wherein the density ratio of the germanium and the nitrogen [Ge/N] satisfies the relationship 0.17<[Ge/N]<1.60.
Zinc oxide free-standing substrate and method for manufacturing same
Disclosed is a self-supporting zinc oxide substrate composed of a plate composed of a plurality of zinc-oxide-based single crystal grains, wherein the plate has a single crystal structure in an approximately normal direction, and the zinc-oxide-based single crystal grains have a cross-sectional average diameter of greater than 1 m. This substrate can be manufactured by a method comprising providing an oriented polycrystalline sintered body; forming a layer with a thickness of 20 m or greater composed of zinc-oxide-based crystals on the oriented polycrystalline sintered body so that the layer has crystal orientation mostly in conformity with crystal orientation of the oriented polycrystalline sintered body; and removing the oriented polycrystalline sintered body to obtain the self-supporting zinc oxide substrate. The present invention can provide a self-supporting zinc oxide substrate being inexpensive and also suitable for having a large area as a preferable alternative material for a zinc oxide single crystal substrate.
Zinc oxide free-standing substrate and method for manufacturing same
Disclosed is a self-supporting zinc oxide substrate composed of a plate composed of a plurality of zinc-oxide-based single crystal grains, wherein the plate has a single crystal structure in an approximately normal direction, and the zinc-oxide-based single crystal grains have a cross-sectional average diameter of greater than 1 m. This substrate can be manufactured by a method comprising providing an oriented polycrystalline sintered body; forming a layer with a thickness of 20 m or greater composed of zinc-oxide-based crystals on the oriented polycrystalline sintered body so that the layer has crystal orientation mostly in conformity with crystal orientation of the oriented polycrystalline sintered body; and removing the oriented polycrystalline sintered body to obtain the self-supporting zinc oxide substrate. The present invention can provide a self-supporting zinc oxide substrate being inexpensive and also suitable for having a large area as a preferable alternative material for a zinc oxide single crystal substrate.
Method for producing crystal of silicon carbide, and crystal production device
Provided is a method that allows growing a single crystal of silicon carbide on an off-substrate of silicon carbide while suppressing surface roughening. The method for producing a crystal of silicon carbide includes rotating a seed crystal of silicon carbide while bringing the seed crystal into contact with a starting material solution containing silicon and carbon. A crystal growth surface of the seed crystal has an off-angle, and the position of a rotation center of the seed crystal lies downstream of the central position of the seed crystal in a step flow direction that is a formation direction of the off-angle.