THE EFFECTS OF WAFER TOPOGRAPHY AFTER STI FILL ON CERIA SLURRY CMP FOR BEYOND 110NM GENERATION

摘要

As chip size shrinkage, similar to the pattern density effect, topography effect of STI structure would also strongly influence CMP performance due to STI filling process getting complication. In this paper, the STI topography effect on SiN erosion of direct ceria slurry CMP was studied on four different STI topography structures created by three different fill approaches on 110nm ground rule with AR～4 and ～8, in respectively. Besides, the performances of two kinds of ceria slurry with different selectivity of oxide to SiN were also compared.