Patent ID: 7115520
Filing Date: 2006-10-03
Classification: H01J,H01L,Y10T

Abstract:
1. A method for anisotropically etching a feature in a substrate comprising the steps of: subjecting the substrate to an alternating cyclical process within a plasma chamber, said alternating cyclical process having an etching step and a deposition step; introducing into said plasma chamber a first process gas for depositing a film onto the substrate during the deposition step of said alternating cyclical process; introducing into said plasma chamber a second process gas for etching the substrate during the etching step of said alternating cyclical process; regulating pressure of said plasma chamber by setting a throttle valve at a predetermined position set point for a period of about 0.05 to 0.5 seconds during at least one step of said alternating cyclical process; igniting a plasma for a recipe period of time for the deposition step of said alternating cyclical process and the etching step of said alternating cyclical process; enabling a closed loop pressure control algorithm after said predetermined period of time expires; and controlling pressure at a recipe specified pressure set point in said plasma chamber through a closed loop pressure control for a period that lasts the remaining time of the step.