Disclosed is a semiconductor device having a substrate, an interfacial layer formed on said substrate, a nitrogen-containing high dielectric constant (high-k) layer formed on said interfacial layer, and a metal electrode on said nitrogen-containing high-k layer. Also disclosed is a method of forming a transistor including forming on a substrate an interfacial layer comprising silicon and oxygen, depositing on the interfacial layer a high-k dielectric material, nitriding the high-k dielectric material, depositing a metal layer on the high-k dielectric material, and patterning the metal layer, the high-k dielectric material, and the interfacial layer to form a gate stack.