Ultrathin nitrogen-profile engineered gate dielectric films

Abstract

A simple and novel scheme is presented for the formation of /spl sim/4 nm gate dielectric films with nitrogen at the top (gate electrode/dielectric) interface. It consists of low-temperature, remote, high-density N/sub 2/-plasma nitridation of thermal SiO/sub 2/, followed by a post-nitridation anneal. The key results are: (a) high N concentrations (10-20 at.%) incorporated uniformly within /spl sim/0.7 nm of the oxide surface, (b) little V/sub fb/-shift and no significant variation in midgap-D/sub it/ from that of control oxide, (c) suppression of B-penetration for high B levels and for high thermal budgets including a hydrogen ambient, and (d) no evidence of damage to the oxide.