Patent ID: 6174740
Filing Date: 2001-01-16
Classification: G01N,H01L

Abstract:
A method of analyzing impurities in a bulk of a silicon wafer, comprising the steps of:applying a mechanical damage onto one major surface of said silicon wafer to introduce distortions therein to form distorted layer;subjecting the silicon wafer to a thermal oxidation process to form a thermal oxide film on the wafer surface where said distorted layer is formed thereon;dissolving only said thermal oxide film with a chemical solution or vapor to recover a dissolved solution; and analyzing said recovered solution; anddetermining bulk impurities of the wafer;wherein said step of subjecting the silicon wafer to a thermal oxidation process to form thermal oxide film on the wafer surface said distorted layer is formed thereon is carried out by annealing said silicon wafer in the presence of an oxygen gas at a temperature of from 300.degree. C. to 650.degree. C. both inclusive for 2-120 minutes.