A CMOS device is provided which comprises (a) a substrate (103); (b) a gate dielectric layer (107) disposed on the substrate, the gate dielectric comprising a metal oxide; (c) an NMOS electrode (105) disposed on a first region of said gate dielectric; and (d) a PMOS electrode (115) disposed on a second region of said gate dielectric, the PMOS electrode comprising a conductive metal oxide; wherein the surface of said second region of said gate dielectric comprises a material selected from the group consisting of metal oxynitrides and metal silicon-oxynitrides.