Plasma processing with phase-locked waveforms

Abstract

A plasma processing method includes applying AC waveforms to a bottom electrode in a plasma chamber to generate a plasma. The method further includes applying a first pulse train including a first plurality of DC pulses to a top electrode in the plasma chamber, where each DC pulse of the first plurality of DC pulses includes a first on-state and a first off-state. And the method further includes applying a second pulse train including a second plurality of DC pulses to the bottom electrode in the plasma chamber, and where each DC pulse of the second plurality of DC pulses includes a second on-state and a second off-state, the first pulse train being offset in phase relative to the second pulse train so that each first off-state overlaps with each second on-state.

Dependencies are inferred from the claim text.