Methods of plasma etching and plasma dicing

Abstract

A method is for plasma etching one or more dicing lanes in a silicon substrate having a backside metal layer attached thereto. The method includes performing a main etch using a cyclical plasma etch process in which a deposition step and an etch step are alternately repeated to produce dicing lanes having scalloped sidewalls, and switching to performing a secondary etch using a cyclical plasma etch process in which a deposition step and an etch step are alternately repeated until the backside metal layer is reached. The amount of silicon removed in one etch step during the secondary etch is half or less than half of the amount of silicon removed in one etch step during the main etch.

Dependencies are inferred from the claim text.