Method of polishing semiconductor structures using a two-step chemical mechanical planarization with slurry particles having different particle bulk densities

摘要

The present invention is a method for removing a portion of a liner film and a metallization layer superimposed over the liner film to expose an underlying dielectric layer on a semiconductor wafer. Specifically, at least a portion of the metallization layer is removed by chemical mechanical polishing the metallization layer using a first polishing slurry having a plurality of first abrasive particles and at least a portion of the liner film is removed by chemical mechanical polishing the liner film using a second polishing slurry having a plurality of second abrasive particles. The first abrasive particles and the second abrasive particles used in the polishing steps have different bulk densities.