Oxide etch

摘要

A new process for plasma etching silicon oxides in integrated circuit structures. A chemistry comprising both oxygen and nitrogen trifluoride is used, with oxygen the dominant component. This provides excellent selectivity to silicon. This etch chemistry also erodes photoresist rapidly, so that it is typically used in combination with a hard-masking process. One particular application of this invention is in a cantilever-etch-mask contact profiling process.