Trace metal contamination analysis of wafer edge and bevel by automated VPD ICP-MS: CFM: Contamination free manufacturing

Abstract

Wafer edge exclusion zone does not constitute any active usable die; nevertheless, it is a source of contamination as it comes into contact with processing equipment. Transition to copper interconnects and low-k dielectrics as well as decreasing gate lengths in Semiconductor manufacturing have resulted in bigger yield hits due to microcontamination from edge exclusion zone. The difficulty of evaluating contamination from edge and bevel of a wafer is well known even as the importance of contamination from these areas has increased. In this study, we will highlight the tools and the methods that we have employed in addressing this problem. We will also share the method detection limits and spike recoveries of trace metals achieved from silicon wafer bevel and edge through Inductively Coupled Plasma Mass Spectrometry (ICP-MS).