Process for depositing and developing a plasma polymerized organosilicon photoresist film

摘要

A process for etching a PPMS layer that increases the etch selectivity of PPMS relative to PPMSO from an initial low etch selectivity to a higher etch selectivity at a later stage of the etching process. In some embodiments, the etch selectivity used during a first etching step of the process is less than 4:1 and the etch selectivity used during a second etching step, subsequent to the first step, is greater than 5:1. In some other embodiments, the etch selectivity of the first step is between 2-3:1 and the etch selectivity of the second step is greater than 8:1. Optionally, in still other embodiments a third etching step, performed between the first and second etching steps may be employed where the etch selectivity is between 3-8:1.