A New Approach for the Study of Chemical Mechanical Polishing

Abstract

The process of chemical mechanical polishing (CMP) can be studied using in situ atomic force microscopy (AFM) by intentionally using a high tip/sample interaction force. The nominal removal rate of Al during AFM scratching is studied under a range of conditions including varying tip/sample force, solution pH, and electrode potential. This approach should be useful for CMP process development and furthering the fundamental understanding of CMP mechanisms. INTRODUCTION The process of chemical mechanical polishing (CMP) of metal involves hard particles suspended in an aqueous slurry that interact with a metal surface because of mechanical force applied between the particles and surface by the polishing pad (1,2). The interaction may result in physical removal of metal or just breaking of a surface film, followed by electrochemical dissolution and reformation of a protective film. In order to understand better the mechanism of CMP, it is instructive to consider the process at its most...