According to the present invention, there is provided a SiC epitaxial wafer including: a 4H-SiC single crystal substrate which has a surface with an off angle with respect to a c-plane as a main surface and a bevel part on a peripheral part; and a SiC epitaxial layer having a film thickness of 20 μm or more, which is formed on the 4H-SiC single crystal substrate, in which a density of an interface dislocation extending from an outer peripheral edge of the SiC epitaxial layer is 10 lines/cm or less.

A method for manufacturing a group III nitride substrate is described. The method involves forming group III nitride films having a group III element face on a surface thereof, on both surfaces of a substrate, so as to produce a group III nitride film carrier. The group III nitride film carrier is subjected to ion implantation and adhered to a base substrate containing polycrystals containing a group III nitride as a major component. The group III nitride film carrier is spaced from the base substrate to transfer the ion-implanted region to the base substrate, so as to form a group III nitride film having an N face on a surface thereof on the base substrate. A group III nitride film is formed on the group III nitride by a THVPE method, so as to produce a thick film of a group III nitride film.

A method for manufacturing a group III nitride substrate is described. The method involves forming group III nitride films having a group III element face on a surface thereof, on both surfaces of a substrate, so as to produce a group III nitride film carrier. The group III nitride film carrier is subjected to ion implantation and adhered to a base substrate containing polycrystals containing a group III nitride as a major component. The group III nitride film carrier is spaced from the base substrate to transfer the ion-implanted region to the base substrate, so as to form a group III nitride film having an N face on a surface thereof on the base substrate. A group III nitride film is formed on the group III nitride by a THVPE method, so as to produce a thick film of a group III nitride film.

A method of manufacturing a diamond substrate includes: forming an ion implantation layer at a side of a main surface of a diamond seed substrate by implanting ions into the main surface of the diamond seed substrate; producing a diamond structure by growing a diamond growth layer by a vapor phase synthesis method on the main surface of the diamond seed substrate, after implanting the ions; and performing heat treatment on the diamond structure. The performed heat treatment causes the diamond structure to be separated along the ion implantation layer into a first structure including the diamond seed substrate and failing to include the diamond growth layer, and a diamond substrate including the diamond growth layer. Thus, the method of manufacturing a diamond substrate is provided that enables a diamond substrate with a large area to be manufactured in a short time and at a low cost.

A method of manufacturing a diamond substrate includes: forming an ion implantation layer at a side of a main surface of a diamond seed substrate by implanting ions into the main surface of the diamond seed substrate; producing a diamond structure by growing a diamond growth layer by a vapor phase synthesis method on the main surface of the diamond seed substrate, after implanting the ions; and performing heat treatment on the diamond structure. The performed heat treatment causes the diamond structure to be separated along the ion implantation layer into a first structure including the diamond seed substrate and failing to include the diamond growth layer, and a diamond substrate including the diamond growth layer. Thus, the method of manufacturing a diamond substrate is provided that enables a diamond substrate with a large area to be manufactured in a short time and at a low cost.

A process for manufacturing a composite structure comprises: a) providing an initial substrate made of monocrystalline silicon carbide, b) epitaxially growing a monocrystalline silicon carbide donor layer on the initial substrate to form a donor substrate 111, c) implanting ions into the donor layer to form a buried brittle plane defining the the donor layer, d) depositing, using liquid injection-chemical vapor deposition at a temperature below 1000° C., a carrier layer on the donor layer, the carrier layer comprising an at least partially amorphous SiC matrix, e) separating the donor substrate along the brittle plane to form an intermediate composite structure comprising the donor layer on the carrier layer f) heat treating the intermediate composite structure at a temperature of between 1000° C. and 1800° C. to crystallize the carrier layer and form the polycrystalline carrier substrate, and g) applying mechanical and/or chemical treatment(s) of the composite structure.

A process for manufacturing a composite structure comprises: a) providing an initial substrate made of monocrystalline silicon carbide, b) epitaxially growing a monocrystalline silicon carbide donor layer on the initial substrate to form a donor substrate 111, c) implanting ions into the donor layer to form a buried brittle plane defining the the donor layer, d) depositing, using liquid injection-chemical vapor deposition at a temperature below 1000° C., a carrier layer on the donor layer, the carrier layer comprising an at least partially amorphous SiC matrix, e) separating the donor substrate along the brittle plane to form an intermediate composite structure comprising the donor layer on the carrier layer f) heat treating the intermediate composite structure at a temperature of between 1000° C. and 1800° C. to crystallize the carrier layer and form the polycrystalline carrier substrate, and g) applying mechanical and/or chemical treatment(s) of the composite structure.

A method deposits an epitaxial layer on a front side of a semiconductor wafer having monocrystalline material. The method includes: providing the semiconductor wafer; arranging the semiconductor wafer on a susceptor; heating the semiconductor wafer to a deposition temperature using thermal radiation directed to the front side and to the rear side of the semiconductor wafer; conducting a deposition gas over the front side of the semiconductor wafer; and selectively reducing an intensity of a portion of the thermal radiation that is directed to the rear side of the semiconductor wafer, as a result of which first partial regions at an edge of the semiconductor wafer, in the first partial regions a growth rate of the epitaxial layer is greater than in adjacent second partial regions given uniform temperature of the semiconductor wafer owing to an orientation of the monocrystalline material, are heated more weakly.

A silicon carbide wafer has one surface and the other surface opposite to the one surface. An average Rmax roughness of the one surface is 2.0 nm or less, and an average Ra roughness of the one surface is 0.1 nm or less. An edge region is a region in which a distance from an edge of the silicon carbide wafer toward a center is 5% to 75% of a radius of the silicon carbide wafer, and a central region is a region having a radius of 25% of the radius of the silicon carbide wafer at the center of the silicon carbide wafer. A difference between an average Rmax roughness of the edge region of the one surface and an average Rmax roughness of the central region of the one surface is 0.01 nm to 0.5 nm.

A silicon carbide wafer has one surface and the other surface opposite to the one surface. An average Rmax roughness of the one surface is 2.0 nm or less, and an average Ra roughness of the one surface is 0.1 nm or less. An edge region is a region in which a distance from an edge of the silicon carbide wafer toward a center is 5% to 75% of a radius of the silicon carbide wafer, and a central region is a region having a radius of 25% of the radius of the silicon carbide wafer at the center of the silicon carbide wafer. A difference between an average Rmax roughness of the edge region of the one surface and an average Rmax roughness of the central region of the one surface is 0.01 nm to 0.5 nm.