US Patent 7521381 Method for producing silicon wafer and silicon wafer

A silicon wafer is thermal-annealed in an atmosphere to form new vacancies therein by thermal annealing and the atmosphere in the thermal annealing contains a nitride gas having a lower decomposition temperature than a decomposable temperature of N2 so that the thermal annealing is carried out at a lower temperature or for a short time to suppress generation of slip and to provide satisfactory surface roughness.