Use of a silicon wafer for manufacturing a semiconductor device in a semiconductor device manufacturing process which conducts heat treatment under conditions of a maximum temperature of 1100°C and a rate of temperature increase of 300°C/sec after subjecting the silicon wafer to mirror machining, wherein the silicon wafer was sliced from a silicon monocrystal ingot grown by the Czochralski method so as to be free of grown-in defects in the body portion of the ingot by pulling up the ingot within a prescribed range of speed and setting intracrystalline temperature distribution immediately after solidification during pulling up within a temperature range from the melting point to 1250°C so that the crystal periphery temperature is smaller than the crystal center temperature, a target diameter of the body portion being set at 200 mm, the axial temperature gradient of the interior of the monocrystal during growth within a range from the melting point to 1370°C, the central portion being set to 3.0-3.2°C/mm and the peripheral portion to 2.3-2.5°C/mm, and the monocrystal was grown by having a pull-up speed undergo a change of 0.6 mm/min to 0.3 mm/min to 0.6 mm/min, the silicon monocrystal ingot has an oxygen concentration of 11.4-12.6×10 17 atoms/cc (old ASTM), (i) the silicon wafer was excised from an area grown as an interstitial-silicon-dominant defect-free region in the monocrystal ingot and the silicon wafer has an oxygen precipitate density of 1 × 10 4 /cm 2 across the entire surface in the radial direction of the silicon wafer; or (ii) the silicon wafer was excised from a location in the monocrystal ingot where a vacancy-dominant defect-free region and an interstitial-silicon-dominant defect-free region intermixed and the silicon wafer has a vacancy-dominant defect-free region from the wafer center to 30 mm and, outside of the vacancy-dominant defect-free region, an interstitial-silicon-dominant defect-free region with an oxygen precipitate density of 1 × 10 4 /cm 2, the interstitial-silicon-dominant defect-free region and the vacancy-dominant defect-free region are free of grown-in defects, to determine whether it is an interstitial-silicon-dominant defect-free region or a vacancy-dominant defect-free region, a wafer excised from the silicon ingot is subjected to heat treatment of 800°C × 4 hours and 1000°C × 16 hours in a dry oxygen atmosphere, 2 μm of light etching is conducted after cleaving the wafer, the density of the oxygen precipitate is measured, and a region where oxygen precipitate density of 5 × 10 4 /cm 2 or less is observed is defined as an interstitial-silicon-dominant defect-free region, and a region where oxygen precipitate density in excess of 5 × 10 4 /cm 2 is observed is defined as a vacancy-dominant defect-free region, and a layer which has a light scattering defect density of 2 × 10 5 /cm 3 or less according to the 90° light scattering method is formed in a region at a depth of 50 μm to 310 μm from the wafer surface, and the 90° light scattering method is conducted by the incidence of light of 1.06 μm wavelength of 1W output from the surface side of the silicon wafer and the detection of 90° scattered light detected from a cleaved surface of the wafer. (i) the silicon wafer was excised from an area grown as an interstitial-silicon-dominant defect-free region in the monocrystal ingot and the silicon wafer has an oxygen precipitate density of 1 × 10 4 /cm 2 across the entire surface in the radial direction of the silicon wafer; or (ii) the silicon wafer was excised from a location in the monocrystal ingot where a vacancy-dominant defect-free region and an interstitial-silicon-dominant defect-free region intermixed and the silicon wafer has a vacancy-dominant defect-free region from the wafer center to 30 mm and, outside of the vacancy-dominant defect-free region, an interstitial-silicon-dominant defect-free region with an oxygen precipitate density of 1 × 10 4 /cm 2, the interstitial-silicon-dominant defect-free region and the vacancy-dominant defect-free region are free of grown-in defects, to determine whether it is an interstitial-silicon-dominant defect-free region or a vacancy-dominant defect-free region, a wafer excised from the silicon ingot is subjected to heat treatment of 800°C × 4 hours and 1000°C × 16 hours in a dry oxygen atmosphere, 2 μm of light etching is conducted after cleaving the wafer, the density of the oxygen precipitate is measured, and a region where oxygen precipitate density of 5 × 10 4 /cm 2 or less is observed is defined as an interstitial-silicon-dominant defect-free region, and a region where oxygen precipitate density in excess of 5 × 10 4 /cm 2 is observed is defined as a vacancy-dominant defect-free region, and a layer which has a light scattering defect density of 2 × 10 5 /cm 3 or less according to the 90° light scattering method is formed in a region at a depth of 50 μm to 310 μm from the wafer surface, and the 90° light scattering method is conducted by the incidence of light of 1.06 μm wavelength of 1W output from the surface side of the silicon wafer and the detection of 90° scattered light detected from a cleaved surface of the wafer.