Method for etching metal lines with enhanced profile control

摘要

The present invention discloses a method for enhancing profile control in a metal line etching process in which a main etching step and an over etching step are used by incorporating a charge neutralization step for the photoresist layer by an inert gas plasma such that plasma ions aimed at the horizontal surface on the semiconductor substrate is not distorted to bombard the sidewalls on the metal lines. The anisotropic etching of the metal lines is improved to provide metal lines on a device that has enhanced profile control and without the void or cavity defect.