Abstract

In this paper we report on applications of scatterometry to obtain better control during silylation. It has come to our attention that semiconductor device manufacturers have experienced inadequate process control during some stages of the manufacturing cycle. Traditional metrological techniques like SEM can often only be used after the final stages. It is hard to deduce which stage, or process parameter lacks precision or needs to be better controlled. We propose scatterometry as an accurate and versatile monitor for almost every stage. We demonstrate its sensitivity by examining diffraction patterns from supposedly identical wafers. Variations in diffraction patterns indicate lack of process control. Furthermore effects of each stage in the processing can be isolated, monitored and examined.

© 1993 Optical Society of America