Impact of diffusionless anneal using dynamic surface anneal on the electrical properties of a high-k/metal gate stack in metal-oxide-semiconductor devices

Abstract

The impact of diffusionless anneal using dynamic surface anneal (DSA) on the electrical properties of p-type metal-oxide-semiconductor devices with high-k gate dielectrics and metal gate was investigated by monitoring flatband voltage (V(FB)) and equivalent oxide thickness (EOT) change. Compared to rapid thermal anneal, DSA induces a positive V(FB) shift without EOT degradation. This finding is attributed to suppression of positively charged oxygen vacancies [V(o)(++)] generation in high-k dielectrics due to the shorter thermal budget. Processing parameters including high-k dielectrics, TiN metal gate thickness, and Si cap deposition temperature significantly affect thermally induced-oxygen vacancies, leading to different V(FB) behaviors.