Gas phase particle reduction in pecvd chamber

Abstract

The present disclosure relates to methods and apparatus for reducing particle contamination on substrates in a plasma process chamber. In one embodiment, by applying a DC power to an electrode surrounding a processing region, the boundary of a plasma region formed in the processing region extends closer to the chamber body and outside of the diameter of the substrate support. In another embodiment, by applying a negative bias to an electrode or a positive bias to the lid, negatively charged species located at the boundary of the plasma region are lifted by the electrostatic force created by the negative bias or the positive bias. As a result, species located at the boundary of the plasma region will not fall onto the edge of the substrate disposed on the substrate support as the electric power for sustaining the plasma region is turned off, leading to reduced particle contamination on the substrate.

Dependencies are inferred from the claim text.