Abstract: According to one embodiment, a method of producing a SiC laminate having a hexagonal SiC layer and a 3C-SiC layer comprises: forming a seed plane parallel to a close-packed plane of the crystal lattice on the surface of the hexagonal SiC layer; providing an inclined plane, which is inclined with respect to the seed plane, to all faces adjacent to the seed plane; forming a two-dimensional nucleus of 3C-SiC on the seed plane; and epitaxially growing both the two-dimensional nucleus of 3C-SiC and the SiC layers exposed on the inclined plane simultaneously in a direction parallel to the close-packed plane of the crystal lattice.

Abstract: A silicon carbide substrate production method includes: the step of providing covering layers 1b, 1b, each containing silicon oxide, silicon nitride, silicon carbonitride, or silicide, respectively on both surfaces of a base material substrate 1a carbon, silicon or silicon carbide, and turning the surface of each of the covering layers 1b, 1b into a smooth surface to prepare a support substrate 1; a step of forming a polycrystalline silicon carbide film 10 on both surfaces of the support substrate 1 by a gas phase growth method or a liquid phase growth method; and a step of separating the polycrystalline silicon carbide films from the support substrate while preserving, on the surface thereof, the smoothness of the covering layer surfaces 1b, 1b by chemically removing at least the covering layers 1b, 1b, from the support substrate 1. The silicon carbide substrate has a smooth surface and reduced internal stress.

Abstract: Provided is an SiC composite substrate 10 having a monocrystalline SiC layer 12 on a polycrystalline SiC substrate 11, wherein: some or all of the interface at which the polycrystalline SiC substrate 11 and the monocrystalline SiC layer 12 are in contact is an unmatched interface I12/11 that is not lattice-matched; the monocrystalline SiC layer 12 has a smooth obverse surface and has, on the side of the interface with the polycrystalline SiC substrate 11, a surface that has more pronounced depressions and projections than the obverse surface; and the close-packed plane (lattice plane 11p) of the crystals of the polycrystalline SiC in the polycrystalline SiC substrate 11 is randomly oriented with reference to the direction of a normal to the obverse surface of the monocrystalline SiC layer 12. The present invention improves the adhesion between the polycrystalline SiC substrate and the monocrystalline SiC layer.

Abstract: A compound semiconductor laminate substrate comprising two single-crystalline compound semiconductor substrates directly bonded together and laminated, the single-crystalline compound semiconductor substrates having the same composition including A and B as constituent elements and having the same atomic arrangement, characterized in that the front and back surfaces of the laminate substrate are polar faces comprising the same kind of atoms of A or B, and that a laminate interface comprises a bond of atoms of either B or A and is a unipolar anti-phase region boundary plane in which the crystal lattices of the atoms are matched. In this way, the polar faces of the front and rear surfaces of the compound semiconductor laminate substrate are made monopolar, thereby facilitating semiconductor element process designing, and making it possible to manufacture a low-cost, high-performance, and stable semiconductor element without implementing complex substrate processing.

Abstract: A manufacturing method of an SiC composite substrate 10 that includes a single crystal SiC layer 12 on a polycrystalline SiC substrate 11. After manufacturing a single crystal SiC layer supporting body 14 by providing the single crystal SiC layer 12 on one surface of a holding substrate 21 including Si. A polycrystalline SiC is deposited on the single crystal SiC layer 12 through chemical vapor deposition to manufacture an SiC laminated body 15 laminated with the single crystal SiC layer 12 and the polycrystalline SiC layer 11 having a thickness t on the holding substrate 21?. At the same time, the single crystal SiC layer supporting body 14 is heated at a temperature less than 1,414 degrees Celsius, and a portion of the thickness t of the polycrystalline SiC is deposited. Then, the holding substrate 21? is physically and/or chemically removed.

Abstract: Provided is an SiC composite substrate 10 having a monocrystalline SiC layer 12 on a polycrystalline SiC substrate 11, wherein: some or all of the interface at which the polycrystalline SiC substrate 11 and the monocrystalline SiC layer 12 are in contact is an unmatched interface I12/11 that is not lattice-matched; the monocrystalline SiC layer 12 has a smooth obverse surface and has, on the side of the interface with the polycrystalline SiC substrate 11, a surface that has more pronounced depressions and projections than the obverse surface; and the close-packed plane (lattice plane 11p) of the crystals of the polycrystalline SiC in the polycrystalline SiC substrate 11 is randomly oriented with reference to the direction of a normal to the obverse surface of the monocrystalline SiC layer 12. The present invention improves the adhesion between the polycrystalline SiC substrate and the monocrystalline SiC layer.

Abstract: Provided is an SiC composite substrate 10 having a monocrystalline SiC layer 12 on a polycrystalline SiC substrate 11, wherein: some or all of the interface at which the polycrystalline SiC substrate 11 and the monocrystalline SiC layer 12 are in contact is an unmatched interface I12/11 that is not lattice-matched; the monocrystalline SiC layer 12 has a smooth obverse surface and has, on the side of the interface with the polycrystalline SiC substrate 11, a surface that has more pronounced depressions and projections than the obverse surface; and the close-packed plane (lattice plane 11p) of the crystals of the polycrystalline SiC in the polycrystalline SiC substrate 11 is randomly oriented with reference to the direction of a normal to the obverse surface of the monocrystalline SiC layer 12. The present invention improves the adhesion between the polycrystalline SiC substrate and the monocrystalline SiC layer.

Abstract: Provided is a method for manufacturing an SiC composite substrate 10 having a single-crystal SiC layer 12 on a polycrystalline SiC substrate 11, wherein: the single-crystal SiC layer 12 is provided on one surface of a holding substrate 21 comprising Si, and a single-crystal SiC-layer carrier 14 is prepared; polycrystalline SiC is then accumulated on the single-crystal SiC layer 12 by a physical or chemical means, and an SiC laminate 15 is prepared in which the single-crystal SiC layer 12 and the polycrystalline SiC substrate 11 are laminated on the holding substrate 21; and the holding substrate 21 is then physically and/or chemically removed. With the present invention, an SiC composite substrate having a single-crystal. SiC layer with good crystallinity is obtained with a simple manufacturing process.

Abstract: A compound semiconductor laminate substrate comprising two single-crystalline compound semiconductor substrates directly bonded together and laminated, the single-crystalline compound semiconductor substrates having the same composition including A and B as constituent elements and having the same atomic arrangement, characterized in that the front and back surfaces of the laminate substrate are polar faces comprising the same kind of atoms of A or B, and that a laminate interface comprises a bond of atoms of either B or A and is a unipolar anti-phase region boundary plane in which the crystal lattices of the atoms are matched. In this way, the polar faces of the front and rear surfaces of the compound semiconductor laminate substrate are made monopolar, thereby facilitating semiconductor element process designing, and making it possible to manufacture a low-cost, high-performance, and stable semiconductor element without implementing complex substrate processing.

Abstract: A silicon carbide substrate production method includes: the step of providing covering layers 1b, 1b, each containing silicon oxide, silicon nitride, silicon carbonitride, or silicide, respectively on both surfaces of a base material substrate 1a carbon, silicon or silicon carbide, and turning the surface of each of the covering layers 1b, 1b into a smooth surface to prepare a support substrate 1; a step of forming a polycrystalline silicon carbide film 10 on both surfaces of the support substrate 1 by a gas phase growth method or a liquid phase growth method; and a step of separating the polycrystalline silicon carbide films from the support substrate while preserving, on the surface thereof, the smoothness of the covering layer surfaces 1b, 1b by chemically removing at least the covering layers 1b, 1b, from the support substrate 1. The silicon carbide substrate has a smooth surface and reduced internal stress.

Abstract: A method for producing a SiC composite substrate 10 having a single crystal SiC layer 12 on a polycrystalline SiC substrate 11. After the single crystal SiC layer 12 is provided on the front surface of a holding substrate 21 including Si and having a silicon oxide film 21a on the front and back surfaces thereof to produce a single crystal SiC layer supporting body 14, a part or all of the thickness of the silicon oxide film 21a on one area or all of the back surface of the holding substrate 21 in the single crystal SiC layer supporting body 14 is removed to impart warpage to the single crystal SiC layer supporting body 14?. Then, polycrystalline SiC is deposited on the single crystal SiC layer 12 by chemical vapor deposition to form the polycrystalline SiC substrate 11, and the holding substrate is physically and/or chemically removed.

Abstract: A method for producing a SiC composite substrate 10 having a single crystal SiC layer 12 on a polycrystalline SiC substrate 11. After the single crystal SiC layer 12 is provided on the front surface of a holding substrate 21 including Si and having a silicon oxide film 21a on the front and back surfaces thereof to produce a single crystal SiC layer supporting body 14, a part or all of the thickness of the silicon oxide film 21a on one area or all of the back surface of the holding substrate 21 in the single crystal SiC layer supporting body 14 is removed to impart warpage to the single crystal SiC layer supporting body 14?. Then, polycrystalline SiC is deposited on the single crystal SiC layer 12 by chemical vapor deposition to form the polycrystalline SiC substrate 11, and the holding substrate is physically and/or chemically removed.

Abstract: Provided is a method for manufacturing an SiC composite substrate 10 having a single-crystal SiC layer 12 on a polycrystalline SiC substrate 11, wherein: the single-crystal SiC layer 12 is provided on one surface of a holding substrate 21 comprising Si, and a single-crystal SiC-layer carrier 14 is prepared; polycrystalline SiC is then accumulated on the single-crystal SiC layer 12 by a physical or chemical means, and an SiC laminate 15 is prepared in which the single-crystal SiC layer 12 and the polycrystalline SiC substrate 11 are laminated on the holding substrate 21; and the holding substrate 21 is then physically and/or chemically removed. With the present invention, an SiC composite substrate having a single-crystal. SiC layer with good crystallinity is obtained with a simple manufacturing process.

Abstract: Provided is an SiC composite substrate 10 having a monocrystalline SiC layer 12 on a polycrystalline SiC substrate 11, wherein: some or all of the interface at which the polycrystalline SiC substrate 11 and the monocrystalline SiC layer 12 are in contact is an unmatched interface I12/11 that is not lattice-matched; the monocrystalline SiC layer 12 has a smooth obverse surface and has, on the side of the interface with the polycrystalline SiC substrate 11, a surface that has more pronounced depressions and projections than the obverse surface; and the close-packed plane (lattice plane 11p) of the crystals of the polycrystalline SiC in the polycrystalline SiC substrate 11 is randomly oriented with reference to the direction of a normal to the obverse surface of the monocrystalline SiC layer 12. The present invention improves the adhesion between the polycrystalline SiC substrate and the monocrystalline SiC layer.

Abstract: A manufacturing method of an SiC composite substrate 10 that includes a single crystal SiC layer 12 on a polycrystalline SiC substrate 11. After manufacturing a single crystal SiC layer supporting body 14 by providing the single crystal SiC layer 12 on one surface of a holding substrate 21 including Si. A polycrystalline SiC is deposited on the single crystal SiC layer 12 through chemical vapor deposition to manufacture an SiC laminated body 15 laminated with the single crystal SiC layer 12 and the polycrystalline SiC layer 11 having a thickness t on the holding substrate 21?. At the same time, the single crystal SiC layer supporting body 14 is heated at a temperature less than 1,414 degrees Celsius, and a portion of the thickness t of the polycrystalline SiC is deposited. Then, the holding substrate 21? is physically and/or chemically removed.