Wafer and epitaxial wafer, and manufacturing processes therefor

Abstract

Provided is a silicon wafer which is stabilized in quality exerting no adverse influence on device characteristics and manufactured by restricting a boron contamination from the environment, and a manufacturing process therefor. Concretely, the silicon wafer is characterized by an attached boron amount thereon being 1×1010 atoms/cm2 or less. In order to manufacture such a wafer as contains a small amount of boron attached on the wafer surface, the wafer is treated in an atmosphere of boron concentration of 15 ng/m3 or less. Boron-less filters and boron adsorbing filters are used as filters in a clean room and the like so as to lower the boron concentration in the atmosphere.

Dependencies are inferred from the claim text.