Removal of impurities from chemical-mechanical polishing slurry in manufacture of semiconductor materials includes using a magnetic filter to remove magnetic particles and then removing non-magnetic particles

摘要

A semiconductor layer on a semiconductor disc is subject to chemical-mechanical polishing (CMP) using a slurry containing particles. Prior to its use, the slurry is filtered first by removal of ferromagnetic particles by a magnetic field. Non ferromagnetic particles are then removed from the slurry by a physical barrier. A suitable assembly has three magnetic field generator units and a physical barrier.