Contact etch in the LAM 4520XL using standard CF/sub 4//CHF/sub 3/ chemistry

Abstract

Summary for ony given, as follows. This paper discusses the specific differences between the 4520XL and the 4520 as pertaining to CD control, uniformity, RIE lag and selectivity. The problems with the current 4520 35MIL and 50MIL dome bottom electrode are also discussed. In addition, the basic trends that have been seen when transferring processes from 4520 to the 4520XL machine using standard analysis of variance (ANOVA) are reviewed. A brief overview of the mechanical differences is shown to explain the two hardware types and the advantages of each. The 4520XL has minimum etch bias (.01), RIE lag is 2x less than the 4520 and consistent from center to edge. On the pattern wafer, the uniformity is 3% better.