Abstract: A plasma etcher for processing a semiconductor wafer and avoid sodium contamination is provided. The etcher includes a chamber having first and second adjoining regions. The etcher further includes a radio frequency source for generating plasma in the first region from delivered gas. A separator is positioned between the first and second regions for transmitting nonionized gas into the second region.

Abstract: A polishing process to planarize a layer formed on a substrate and to reduce the variations in the thickness of that layer from substrate to substrate. The polishing process is implemented by polishing a substrate using a stable pad material. A stable pad material is formed from a polishing material that has substantially the same or similar density, hardness, and compressibility as polyurethane but is a material other than or substantially other than polyurethane. In an alternative embodiment, the material for the polishing pad may be selected for its compression, high tensile strength, wear resistance and/or resistance to water, diluted acids, and alkalis. In a further alternative embodiment, the material forming the polishing pad may be selected from the group comprising hydrogenated nitrile compounds, fluoroelastomers, or perfluoroelastomers.