| 摘要 |
PROBLEM TO BE SOLVED: To provide a silicon semiconductor substrate whose crystal defects liable to cause problems in the manufacturing a device, are efficiently reduced at a low cost without using heat treatment in a hydrogen atmosphere, or the like, and also to provide a production process of the substrate. SOLUTION: This silicon semiconductor substrate (silicon wafer) consists of a silicon single crystal grown by a Czochralski method. The production of the silicon wafer comprises: growing a silicon single crystal at a >=2 deg.C/min cooling rate in the range of from a melt temperature to 800 deg.C of the crystal being grown; slicing a silicon wafer from the grown single crystal; and subjecting the silicon wafer to heat treatment in a rare gas containing <=5 ppm impurities or in a non-oxidizing atmosphere in which the oxide film thickness after the heat treatment is controlled so as to be <=2 nm, at >=1,150 deg.C for >=[73-0.06×temperature ( deg.C)] hr; wherein the defect density of defects each having a >=50 nm size expressed in terms of the diameter, in a deep region having >50μm depth from the surface of the wafer is >=3×106/cm3 and the COP(crystal originated particle) density of particles each having a >=0.1μm size in a shallow region having <1μm depth from the surface of the wafer is <=3×105/cm3.
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