There can be provided a silicon single crystal wafer grown according to Czochralski
method wherein the whole plane of the wafer is occupied by N region on the outside
of OSF generated in a shape of a ring by thermal oxidation treatment and there
exists no defect region detected by Cu deposition. Thereby, there can be produced
a silicon single crystal wafer according to CZ method, which does not belong to
any of V region rich in vacancies, OSF region and I region rich in interstitial
silicons, and can surely improve electric characteristics such as oxide dielectric
breakdown voltage characteristics or the like under stable manufacture conditions.
