Patent ID: 9244019
Filing Date: 2016-01-26
CPC Classification: G01N,H01L

Claim Text:
1. A method for measuring defects in a silicon substrate obtained by silicon ingot pulling, wherein the defects have a size of less than 20 nm, the method comprising: applying a first defect consolidation heat treatment to the silicon substrate at a temperature of between 750° C. and 850° C. for a time period of between 30 minutes and 1 hour to consolidate defects having a size of less than 20 nm in the silicon substrate, under an atmosphere consisting of at least one of argon and nitrogen, without generating additional defects; applying a second defect enlargement heat treatment to the silicon substrate at a temperature of between 900° C. and 1,000° C. for a time period of between 1 hour and 10 hours to enlarge the defects having a size of less than 20 nm in the silicon substrate to a size of greater than or equal to 20 nm, with the enlarged defects containing oxygen precipitates, under an atmosphere consisting of at least one of argon and nitrogen, without generating additional defects; measuring size and density of the enlarged defects in a surface layer of the silicon substrate; and calculating the initial size of the defects on the basis of the measurements of the enlarged defects; wherein the silicon substrate is maintained at temperatures at or below 1,000° C. throughout the first defect consolidation heat treatment and the second defect enlargement heat treatment.