Lam Research Corporation
Three or more states for achieving high aspect ratio dielectric etch

Abstract:

Systems and methods for applying three or more states for achieving a high aspect ratio dielectric etch operation are described. In one of the methods, a middle state is introduced between a high state and a low state. The middle state is applied to both a source radio frequency (RF) generator and a bias radio frequency (RF) generator. During the middle state, RF power is maintained to be between a high amount of RF power associated with the high state and a low amount of RF power associated with the low state to achieve the high aspect ratio dielectric etch.