Final polish for SOI wafers-surface roughness and TTV degradation

Abstract

We have demonstrated a manufacturable final CMP based process to recover the roughness of as-prepared SOI wafers. The roughness achievable is comparable to prime Si bulk wafers and in keeping with Si wafer requirements for ULSI. Concomitant to the process is some TTV degradation. Our process has been tuned to minimize this degradation and to keep it consistent with CMOS/SOI requirements on TTV.