Application of surface photovoltage method to in-line monitoring of metallic contamination in a manufacturing environment

Abstract

We investigated the correlation between junction degradation of bipolar transistors and heavy metal contamination using the SPV (Surface Photovoltage) method, and found Fe contamination was the main cause of collector-emitter shorts. It was revealed that the source of Fe atoms was a contaminated Si/sub 3/N/sub 4/ film by using the SPV method to analyze contamination levels of equipment. In this regard, the SPV method has proven to be a highly efficient monitoring tool for heavy metal contamination in a manufacturing environment.