Charging damage during contact etch triggered by increased borderless nitride conductivity

Abstract

In this paper we evaluate the effect of nitride conduction on charging damage during contact etch. In particular, it is demonstrated that photoconduction is triggered in silicon nitride films when they are exposed to plasma during contact etch. As a consequence of this increased conductivity, they act as antennas, being able to collect charges from unstable plasmas and inject them into the gate oxide, thus causing charging damage.