Fundamentals of CMP for IC manufacturing: recent progress

Preston's equation, constituting the current basis for CMP process control and consumables development in IC manufacturing, was demonstrated recently to be fundamentally flawed for polishing with soft pads which are usually used in the IC industry. In contrast to the conventional Preston's equation, the pressure dependence of the removal rate (RR) for CMP with soft pads was found to be sublinear, i.e., RR/spl prop/P/sup 2/3/. This paper summarizes this and our other recent progress in CMP fundamentals for IC manufacturing.