Patent ID: 7226850

Claim:
A method for forming a semiconductor structure comprising: growing a layer of AlN on a substrate comprising a compound of silicon, such growing comprising directing a flux of aluminum atoms and a flux of reactive nitrogen atoms onto a surface of the substrate with the reactive nitrogen flux greater than the aluminum flux; and changing the aluminum and reactive nitrogen fluxes such that the aluminum flux is greater than the reactive nitrogen flux; wherein the growing of the layer of AlN on the substrate is with the reactive nitrogen flux greater than the aluminum flux includes growing such layer to a thickness of 30–300 Angstroms; wherein the growing of said layer of AlN is with the aluminum flux greater than the reaction nitrogen flux growing such layer to a thickness of 50–1000 Angstroms; including: subsequently growing a graded Al x Ga 1-x N layer including subsequently growing an GaN layer; and including subsequently growing an Al x Ga 1-x N layer.