Patent ID: 8324005

Claim:
A method of forming a semiconductor structure, comprising: forming a first layer of a nitride semiconductor material; forming a substantially relaxed nitride interlayer on the first layer of nitride semiconductor material, the substantially relaxed nitride interlayer having a first lattice constant, wherein the nitride interlayer comprises aluminum and gallium and is conductively doped with an n-type dopant; and forming a second layer of the nitride semiconductor material, wherein the first layer of the nitride semiconductor material, the nitride interlayer, and the second layer of the nitride semiconductor material have a combined thickness of at least about 0.5 μm; forming a plurality of discrete portions in the nitride interlayer, wherein the discrete portions have a material composition that is different than a material composition of the nitride interlayer; wherein the first layer of the nitride semiconductor material is tensile strained; and wherein the nitride semiconductor material has a second lattice constant such that the first layer of nitride semiconductor material is more tensile strained on one side of the substantially relaxed nitride interlayer than the second layer of nitride semiconductor material is on the other side of the substantially relaxed nitride interlayer.