Patent ID: 8835284
Filing Date: 2014-09-16
Classification: C30B,H01L

Abstract:
1. A method of manufacturing an annealed wafer, comprising the steps of: a) growing a silicon single crystal by the Czochralski method from a silicon melt to which nitrogen, carbon, and hydrogen are added in a crystal pulling furnace; b) cutting out a substrate from said silicon single crystal; and c) heat treating said substrate, wherein, during growth of the silicon single crystal in step a), during heat treating in step c), heat treatment is performed in a noble gas atmosphere having an impurity concentration of not more than 5 ppma, or in a non-oxidizing atmosphere in which a film thickness of an oxide film to be formed on a surface of said substrate after the heat treatment is suppressed to not more than 2 nm, at a heating temperature of not less than 1150° C. and not more than 1250° C., for a heating time period of not less than 10 minutes and not more than two hours.