Sacrificial capping layers

摘要

Capping layers can protect porous low-k materials from subsequent processes. Although the introduction of porous low-it dielectrics has been pushed out, there are good reasons to use capping layers now. This article focuses on the impact of using sacrificial cap layers on the copper-barrier CMP process and on CMP consumables selection. Among the CMP-specific benefits of using sacrificial caps are better topography control, process stability, and throughput.