The n-type layer 204 may be formed using conventional deposition techniques, such as metal-organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), or other epitaxial techniques. In an epitaxial deposition process, chemical reactants provided by one or more source gases are controlled and the system parameters are set so that depositing atoms arrive at a deposition surface with sufficient energy to move around on the surface and orient themselves to the crystal arrangement of the atoms of the deposition surface. Accordingly, the n-type layer 204 may be grown on the sapphire substrate 202 using conventional epitaxial techniques. A nucleation layer (not shown) may be formed on the substrate 202 prior to the n-type layer 204. The nucleation layer may comprise GaN or AlN.

The p-type layer 208 may be formed using the conventional epitaxial deposition techniques described above. The p-type layer 208 may comprise any Group III-V semiconductors, including binary, ternary, and quaternary alloys of gallium, aluminum, indium, and nitrogen, also referred to as III-nitride materials. In an example, the p-type layer 208 may comprise GaN. The p-type layer 208 may be doped with p-type dopants, such as Mg. An electron blocking layer (not shown) may be formed below the p-type layer 208.