Method of fabricating stacked N-O-N ultrathin gate dielectric structures

A method of manufacturing a semiconductor device comprising the steps of:

• a) providing a substrate;
• b) providing a field oxide coupled to the substrate;
• c) providing a gate dielectric structure, the gate dielectric structure being composed of a plurality of layers of dielectric material coupled to the substrate and the field oxide, each of the plurality of layers extending across all of the gate dielectric structure, the plurality of layers of dielectric material including a layer of oxynitride having a nitrogen content, the layer of oxynitride being deposited under a pressure using a stream of gas, wherein insensitivity to defects on a surface of the substrate results from the layer of oxynitride, the plurality of layers of dielectric material further including a first layer of oxide under the layer of oxynitride and a second layer of oxide over the layer of oxynitride, wherein at least the first layer of oxide is deposited;
• and
• d) providing a layer of polysilicon over the plurality of layers of dielectric material, wherein a doping substance is implanted in the polysilicon layer, and wherein the nitrogen content impedes diffusion of the doping substance through the gate dielectric structure toward the substrate.