Pattern-Independent PMD Layer Planarization by Controlling its Volume Before CMP

Abstract—We achieved excellent planarization for a pre-metal dielectric (PMD) layer regardless of its pattern density distribution by making the distribution uniform before chemical mechanical polishing (CMP) without any stopper layer. The distribution control was done by lithography using a checkered reticle on the high-density PMD area followed by etching of the PMD layer to uniformize the…