Abstract: A method for manufacturing a single-crystal 4H—SiC substrate includes preparing a 4H—SiC bulk single-crystal substrate having a flat surface, and growing an epitaxial first single-crystal 4H—SiC layer having recesses on the 4H—SiC bulk single-crystal substrate to a thickness X, measured in micrometers (?m). The recesses have a diameter Y, measured in micrometers, no smaller than 0.2*X and no larger than 2*X. In addition, the recesses have a depth Z, when measured in micrometers, no smaller than (0.95*X+0.5*10?3), and no larger than 10*X*10?3.

Abstract: A single-crystal 4H-SiC substrate includes a 4H-SiC bulk single-crystal substrate; and an epitaxial first single-crystal 4H-SiC layer on the 4H-SiC bulk single-crystal substrate and having recesses. The recesses have a diameter no smaller than 2 ?m and no larger than 20 ?m. The recesses have a depth no smaller than 0.01 ?m and no larger than 0.1 ?m. A single-crystal 4H-SiC substrate also includes a 4H-SiC bulk single-crystal substrate; and an epitaxial first single-crystal 4H-SiC layer on the 4H-SiC bulk single-crystal substrate and having recesses. The density of the recesses in the epitaxial first single-crystal 4H-SiC layer is at least 10/cm2, and the epitaxial first single-crystal 4H-SiC layer has a defect density no larger than 2/cm2.

Abstract: A method for manufacturing a single-crystal 4H-SiC substrate includes preparing a 4H-SiC bulk single-crystal substrate having a flat surface, and growing an epitaxial first single-crystal 4H-SiC layer having recesses on the 4H-SiC bulk single-crystal substrate to a thickness X, measured in micrometers (?m). The recesses have a diameter Y, measured in micrometers, no smaller than 0.2*X and no larger than 2*X. In addition, the recesses have a depth Z, when measured in micrometers, no smaller than (0.95*X+0.5*10?3), and no larger than 10*X*10?3.

Abstract: A method for manufacturing a single-crystal 4H-SiC substrate includes: preparing a flat 4H-SiC bulk single-crystal substrate; and epitaxially growing a first single-crystal 4H-SiC layer having recesses on the 4H-SiC bulk single-crystal substrate, wherein the first single-crystal 4H-SiC layer has a thickness of X (?m), the recesses have a diameter Y (?m) no smaller than 0.2*X (?m) and no larger than 2*X (?m), and a depth of Z (nm) no smaller than (0.95*X (?m)+0.5 (nm)) and no larger than 10*X (?m).

Abstract: A measurement target including a semiconductor substrate, and a first epitaxial layer and a second epitaxial layer stacked in this order on the semiconductor substrate and having no difference in refractive index of a real part from the semiconductor substrate is subjected to reflection interference analysis using a Fourier transform infrared spectroscopy. The thickness of the first epitaxial layer is used as a fitting parameter so as to prevent shift between an interference waveform of a resultant reflection interference pattern containing distortion appearing in a wave number range near an abnormal dispersion range of a refractive index caused by phonon absorption and an interference waveform of a numerically calculated reflection interference pattern in the same wave number range. The thickness of the first epitaxial layer determined during the fitting of the numerically calculated reflection interference pattern is defined as a measured value of the thickness of the first epitaxial layer.

Abstract: A method for manufacturing a SiC epitaxial wafer includes: a first step of, by supplying a Si supply gas and a C supply gas, performing a first epitaxial growth on a SiC bulk substrate with a 4H—SiC(0001) having an off-angle of less than 5° as a main surface at a first temperature of 1480° C. or higher and 1530° C. or lower; a second step of stopping the supply of the Si supply gas and the C supply gas and increasing a temperature of the SiC bulk substrate from the first temperature to a second temperature; and a third step of, by supplying the Si supply gas and the C supply gas, performing a second epitaxial growth on the SiC bulk substrate having the temperature increased in the second step at the second temperature.

Abstract: A method for manufacturing a silicon carbide semiconductor device includes: preparing a silicon carbide single crystal substrate having a flatness with an average roughness of 0.2 nm or less; gas-etching a surface of the silicon carbide single crystal substrate under an atmosphere of a reducing gas; and forming a silicon carbide layer on the gas-etched surface of the silicon carbide single crystal substrate, wherein an etching rate of the gas etching is made in a range of 0.5 ?m/hour or faster to 2.0 ?m/hour or slower.

Abstract: A method for manufacturing a single-crystal 4H-SiC substrate includes: preparing a flat 4H-SiC bulk single-crystal substrate; and epitaxially growing a first single-crystal 4H-SiC layer having recesses on the 4H-SiC bulk single-crystal substrate, wherein the first single-crystal 4H-SiC layer has a thickness of X (?m), the recesses have a diameter Y (?m) no smaller than 0.2*X (?m) and no larger than 2*X (?m), and a depth of Z (nm) no smaller than (0.95*X (?m) +0.5 (nm)) and no larger than 10*X (?m).

Abstract: A measurement target including a semiconductor substrate, and a first epitaxial layer and a second epitaxial layer stacked in this order on the semiconductor substrate and having no difference in refractive index of a real part from the semiconductor substrate is subjected to reflection interference analysis using a Fourier transform infrared spectroscopy. The thickness of the first epitaxial layer is used as a fitting parameter so as to prevent shift between an interference waveform of a resultant reflection interference pattern containing distortion appearing in a wave number range near an abnormal dispersion range of a refractive index caused by phonon absorption and an interference waveform of a numerically calculated reflection interference pattern in the same wave number range. The thickness of the first epitaxial layer determined during the fitting of the numerically calculated reflection interference pattern is defined as a measured value of the thickness of the first epitaxial layer.

Abstract: A method is provided in order to manufacture a silicon carbide epitaxial wafer whose surface flatness is very good and has a very low density of carrot defects and triangular defects arising after epitaxial growth. The silicon carbide epitaxial wafer is manufactured by a first step of annealing a silicon carbide bulk substrate that is tilted less than 5 degrees from <0001> face, in a reducing gas atmosphere at a first temperature T1 for a treatment time t, a second step of reducing the temperature of the substrate in the reducing gas atmosphere, and a third step of performing epitaxial growth at a second temperature T2 below the annealing temperature T1 in the first step, while supplying at least a gas including silicon atoms and a gas including carbon atoms.

Abstract: A film of an epitaxial layer that allows the reduction in both the height of a bunching step and crystal defects caused by a failure in migration of reactive species on a terrace is formed on a SiC semiconductor substrate having an off angle of 5 degrees or less. A film of a first-layer epitaxial layer is formed on and in contact with a surface of the SiC semiconductor substrate having an off angle of 5 degrees or less. Subsequently, the temperature in a reactor is lowered. A second-layer epitaxial layer is caused to epitaxially grow on and in contact with a surface of the first-layer epitaxial layer. In the above-described manner, the epitaxial layer is structured with two layers, and the growth temperature for the second epitaxial layer is set lower than the growth temperature for the first epitaxial layer.

Abstract: A method is provided in order to manufacture a silicon carbide epitaxial wafer whose surface flatness is very good and has a very low density of carrot defects and triangular defects arising after epitaxial growth. The silicon carbide epitaxial wafer is manufactured by a first step of annealing a silicon carbide bulk substrate that is tilted less than 5 degrees from <0001> face, in a reducing gas atmosphere at a first temperature T1 for a treatment time t, a second step of reducing the temperature of the substrate in the reducing gas atmosphere, and a third step of performing epitaxial growth at a second temperature T2 below the annealing temperature T1 in the first step, while supplying at least a gas including silicon atoms and a gas including carbon atoms.

Abstract: A film of an epitaxial layer that allows the reduction in both the height of a bunching step and crystal defects caused by a failure in migration of reactive species on a terrace is formed on a SiC semiconductor substrate having an off angle of 5 degrees or less. A film of a first-layer epitaxial layer is formed on and in contact with a surface of the SiC semiconductor substrate having an off angle of 5 degrees or less. Subsequently, the temperature in a reactor is lowered. A second-layer epitaxial layer is caused to epitaxially grow on and in contact with a surface of the first-layer epitaxial layer. In the above-described manner, the epitaxial layer is structured with two layers, and the growth temperature for the second epitaxial layer is set lower than the growth temperature for the first epitaxial layer.

Abstract: A photovideo camera takes visual images formed on negative films and/or positive films to obtain video signals corresponding to the visual images. The camera unit of the photovideo camera can be focused after determining a desired angle of view by zooming, without changing the desired angle of view. In focusing the lens unit, only the master lens of the focusing lens system of the lens unit is moved.

Abstract: A photo video camera device for photographing a visible image on a negative film and/or a positive film developed. The photo video camera device includes a lens barrel, a solid-state image pickup device fixed to the lens barrel, a rotating mechanism for rotating the lens barrel with the solid-state image pickup device, and a supporting member for supporting the lens barrel with the solid-state image pickup device so that the lens barrel and the solid-state image pickup device are rotatable together relative to the supporting member by the rotating mechanism. Accordingly, there occurs no misalignment of axes between a lens system retained in the lens barrel and the solid-state image pickup device, and no dust or the like sticks to the lens system and the solid-state image pickup device.