Semiconductor device having a metal gate electrode formed on an annealed high-k gate dielectric layer

摘要

A method of forming a transistor gate stack having an annealed gate dielectric layer begins by providing a substrate that includes a first and second spacer separated by a trench. A conformal high-k gate dielectric layer is deposited on the substrate and within the trench with a thickness that ranges from 3 Å to 60 Å. Next, a capping layer is deposited on the high-k gate dielectric layer that substantially fills the trench and covers the high-k gate dielectric layer. The high-k gate dielectric layer is then annealed at a temperature that is greater than or equal to 600° C. The capping layer is removed to expose an annealed high-k gate dielectric layer. A metal layer is then deposited on the annealed high-k gate dielectric layer. A CMP process may be used to remove excess material and complete formation of the transistor gate stack.