Patent ID: 7169674

Claim:
A field effect transistor comprising: a substrate comprising a source region, a drain region, and a channel region therebetween; an insulating layer being disposed over said channel region, said insulating layer comprising at least one member selected from the group consisting of Al 2 O 3 , HfO 2 , Y 2 O 3 , Gd 2 O 3 , silicates thereof and aluminates thereof; a diffusion barrier formed on said substrate, said diffusion barrier comprising at least one member selected from the group consisting of aluminum oxynitride, aluminum nitride, silicon nitride and silicon oxynitride; and a gate electrode formed on said diffusion barrier, said diffusion barrier inhibiting a diffusion of dopants from said gate electrode, wherein said diffusion barrier comprises one of: a barrier layer formed between said insulating layer and said substrate; a barrier layer formed within said insulating layer, and other than physically adjacent to said gate electrode; and an additive material distributed within said insulating layer.