Abstract: A SiC epitaxial wafer in which a SiC epitaxial layer is formed on a 4H-SiC single crystal substrate having an off angle and a substrate carbon inclusion density of 0.1 to 6.0 inclusions/cm2, wherein a total density of large pit defects and triangular defects caused by substrate carbon inclusions and contained in the SiC epitaxial layer is 0.01 defects/cm2 or more and 0.6 defects/cm2 or less. The large pit defect is a pit located on a surface at a position corresponding to a position of the carbon inclusion on the substrate surface, and a conversion rate from the substrate carbon inclusions to the large pit defects and the triangular defects caused by the substrate carbon inclusions is 20% or less. Also disclosed is a method for producing the SiC epitaxial wafer.

Abstract: A sensor disposition structure in a seat includes a cushion pad and a board-like member which is disposed under the cushion pad. A concave is formed in an upper surface of the board-like member, and a sensor is disposed in the concave.

Abstract: A SiC single crystal substrate of an embodiment has a diameter being 199 mm or more, wherein the density of threading dislocations per area of 0.25 mm2 arbitrarily selected in the main surface of the SiC single crystal substrate is 5×104/cm2 or less, and the threading dislocations include a threading edge dislocation.

Abstract: 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 ?m 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.

Abstract: 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 ?m 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.

Abstract: A SiC epitaxial wafer in which a SiC epitaxial layer is formed on a 4H—SiC single crystal substrate having an off angle and a substrate carbon inclusion density of 0.1 to 6.0 inclusions/cm2, wherein a total density of large pit defects and triangular defects caused by substrate carbon inclusions and contained in the SiC epitaxial layer is 0.01 defects/cm2 or more and 0.6 defects/cm2 or less. The large pit defect is a pit located on a surface at a position corresponding to a position of the carbon inclusion on the substrate surface, and a conversion rate from the substrate carbon inclusions to the large pit defects and the triangular defects caused by the substrate carbon inclusions is 20% or less. Also disclosed is a method for producing the SiC epitaxial wafer.

Abstract: A SiC epitaxial wafer including a high-concentration epitaxial layer having an impurity concentration of 1×1018 cm?3 or more, and the number or positions of basal plane dislocations included in the high-concentration epitaxial layer have been identified

Abstract: A SiC epitaxial wafer in which a SiC epitaxial layer is formed on a 4H—SiC single crystal substrate having an off angle and a substrate carbon inclusion density of 0.1 to 6.0 inclusions/cm2, and wherein a density of large pit defects caused by substrate carbon inclusions and contained in the SiC epitaxial layer is 0.5 defects/cm2 or less.

Abstract: An evaluation method of a SiC epitaxial wafer includes: a first observation step of preparing a SiC epitaxial wafer having a high-concentration epitaxial layer having an impurity concentration of 1×1018 cm?3 or more, irradiating a surface of the high-concentration epitaxial layer having an impurity concentration of 1×1018 cm?3 or more with excitation light, and observing a surface irradiated with the excitation light via a band-pass filter having a wavelength band of 430 nm or less.

Abstract: A SiC epitaxial wafer in which a SiC epitaxial layer is formed on a 4H-SiC single crystal substrate having an off angle and a substrate carbon inclusion density of 0.1 to 2.5 inclusions/cm2, wherein a total density of large pit defects and triangular defects caused by substrate carbon inclusions and contained in the SiC epitaxial layer is 0.6 defects/cm2 or less.

Abstract: A SiC epitaxial wafer, including: a SiC substrate; and an epitaxial layer stacked on a first surface of the SiC substrate, wherein an area occupied by bar-shaped stacking faults on the first surface of the SiC substrate is identified, and the area occupied by bar-shaped stacking faults on the first surface of the SiC substrate is equal to or less than ¼ of the first surface area of the SiC substrate.

Abstract: A SiC substrate includes a first principal surface, a second principal surface disposed on a side opposite to the first principal surface, and an outer periphery connected to the first principal surface and the second principal surface, wherein a density of composite defects present at a peripheral edge portion of the SiC substrate, in which a hollow portion and a dislocation line extending from the hollow portion are connected to each other is equal to or greater than 0.01 pieces/cm2 and equal to or less than 10 pieces/cm2.

Abstract: A SiC wafer defect measuring method which includes a device management step of managing a defect measuring device by irradiating a reference sample made of a material having a light-emitting intensity that does not change with repeated irradiation by excitation light and which has a pattern made of recesses and/or protrusions in the surface, the irradiation by the excitation light being performed before measuring defects in a SiC wafer and under the same irradiation conditions as the measurement of the defects in the SiC wafer, and then measuring the S/N ratio of the pattern from a reflection image of the pattern.

Abstract: A SiC epitaxial wafer having a SiC epitaxial layer formed on a SiC single crystal substrate having an offset angle of 4 degrees or less in a<11-20>direction from a (0001) plane. A trapezoidal defect included in the SiC epitaxial wafer includes an inverted trapezoidal defect in which a length of a lower base on a downstream side of a step flow is equal to or less than a length of an upper base on an upstream side of the step flow. Also disclosed is a method for manufacturing the SiC epitaxial wafer.

Abstract: A SiC epitaxial wafer, including: a SiC substrate; and an epitaxial layer stacked on a first surface of the SiC substrate, wherein an area occupied by bar-shaped stacking faults on the first surface of the SiC substrate is identified, and the area occupied by bar-shaped stacking faults on the first surface of the SiC substrate is equal to or less than ¼ of the first surface area of the SiC substrate.

Abstract: In a SiC substrate evaluation method, a bar-shaped stacking fault is observed by irradiating a surface of a SiC substrate before stacking an epitaxial layer with excitation light and extracting light having a wavelength range from equal to or greater than 405 nm and equal to or less than 445 nm among photoluminescence light beams emitted from the first surface.

Abstract: 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 ?m 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.

Abstract: In a SiC substrate evaluation method, a bar-shaped stacking fault is observed by irradiating a surface of a SiC substrate before stacking an epitaxial layer with excitation light and extracting light having a wavelength range from equal to or greater than 405 nm and equal to or less than 445 nm among photoluminescence light beams emitted from the first surface.

Abstract: A SIC substrate includes a first principal surface, a second principal surface disposed on a side opposite to the first principal surface, and an outer periphery connected to the first principal surface and the second principal surface, wherein a density of composite defects present at a peripheral edge portion of the SIC substrate, in which a hollow portion and a dislocation line extending from the hollow portion are connected to each other is equal to or greater than 0.01 pieces/cm2 and equal to or less than 10 pieces/cm2.

Abstract: A SiC wafer defect measuring method which includes a device management step of managing a defect measuring device by irradiating a reference sample made of a material having a light-emitting intensity that does not change with repeated irradiation by excitation light and which has a pattern made of recesses and/or protrusions in the surface, the irradiation by the excitation light being performed before measuring defects in a SiC wafer and under the same irradiation conditions as the measurement of the defects in the SiC wafer, and then measuring the S/N ratio of the pattern from a reflection image of the pattern.