Patent ID: 8865581

Claim:
A method of forming a semiconductor device, comprising: providing a substrate containing first and second device regions and an interface layer on the substrate; depositing a first high-k film on the interface layer in the first and second device regions; forming a first cap layer containing a first chemical element on the first high-k film in the first device region; depositing a replacement gate electrode film in the first and second device regions; heat-treating the first high-k film at a first heat-treating temperature to diffuse the first chemical element from the first cap layer into the first high-k film in the first device region to form a first modified high-k film; patterning the replacement gate electrode film in the first and second device regions; forming sidewall spacers adjacent the patterned replacement gate electrode film; removing the patterned replacement gate electrode film to form recessed features defined by the sidewall spacers in the first and second device regions; depositing a second high-k film in the recessed features; heat-treating the second high-k film at a second heat-treating temperature that is lower than the first heat-treating temperature; and depositing a gate metal film on the second high-k film.