High Speed, High Density SPV Mapping of Iron Contamination in Silicon Wafers

摘要

The refined surface photovoltage, minority carrier diffusion length technique provides, for the first time, the fast mapping capability of iron contamination and other recombination center defects in p-type silicon wafers. The method is non-contact and uses an IR-light as the only medium to reach the wafer. Mapping with a density of up to 6000 points/wafer is achieved in about 20 minutes with an Fe detection limit below 10~(10) atoms/cm~3.