A method for fabricating a gate dielectric of a field effect transistor is provided. In one embodiment, the method includes removing a native oxide layer, forming an oxide layer, forming a gate dielectric layer over the oxide layer, forming an oxide layer over the gate dielectric layer, and annealing the layers and underlying thermal oxide/silicon interface. Optionally, the oxide layer may be nitridized prior to forming the gate dielectric layer. In one embodiment, the oxide layer on the substrate is formed by depositing the oxide layer, and the oxide layer on the gate dielectric layer is formed by oxidizing at least a portion of the gate dielectric layer using an oxygen-containing plasma. In another embodiment, the oxide layer on the gate dielectric layer is formed by forming a thermal oxide layer, i.e., depositing the oxide layer on the gate dielectric layer.