Patent ID: 8419958
Filing Date: 2013-04-16
Classification: H01J,H01L,H02N

Abstract:
1. A method for etching a substrate, comprising: contacting a surface of a substrate situated on a support with a plasma within a processing chamber; providing an RF voltage signal to the processing chamber to impose a negative bias on the surface of the substrate relative to the plasma to form an opening in the substrate; generating a constant DC voltage signal that is positive relative to the plasma; and selectively operating a control to switch between an open position that precludes electrical communication between the constant DC voltage signal and the support and a closed position that establishes electrical communication between the constant DC voltage signal and the support to intermittently supply the constant DC voltage signal to the support at an amplitude, frequency, and duration to cause the negative bias on the surface of the substrate to change to a positive bias on the surface of the substrate relative to the plasma.