Universal theory of workfunctions at metal/Hf-based high-k dielectrics interfaces - guiding principles for gate metal selection

We have constructed a universal theory of workfunctions at metal/Hf-based dielectrics interfaces by combining an oxygen vacancy effects and a new concept of generalized charge neutrality level. Our theory systematically reproduces the experimentally observed workfunctions of various gate materials, including the unusual behaviors of workfunctions of both p-metals and metal silicides, and will become a useful guiding principle for the material selection of gate metals