Apparatus for sidewall profile control during an etch process

摘要

A process is provided for controlling the slope of the sidewalls of an opening produced in a semiconductor wafer during an etch process. Microwave or radio frequency energy is remotely applied to pre-excite a process gas. Radio frequency energy is also supplied to the process gas within the process chamber. The sidewall slope is varied by varying the ratio of the amount of remote microwave or radio frequency energy supplied and that of the radio frequency energy supplied within the process chamber. The sidewall slope is also shaped by controlling the process gas flow rate and composition, and the pressure within the process chamber. A more vertical, anisotropic etch profile is obtained with increased radio frequency energy and lower process chamber pressure. A more horizontal, isotropic profile is obtained with decreased radio frequency energy and higher process chamber pressure. A narrower etched feature having smaller interlayer and active element contact regions than the corresponding feature size on the overlying photoresist layer may thereby be provided.