The objective of this proposal is to develop an MOCVD growth process that will allow for the growth of thick, relaxed, doped and undoped, c-oriented AlGaN layers of any composition on the c-plane of native GaN and AlN substrates. Although these AlGaN layers will be relaxed, they will have a dislocation density similar to that of the used native substrates (E3 - E5 cm-2). This will be achieved by growing AlGaN layers on GaN and AlN surfaces with pyramidal facets, allowing for the nucleation of misfit dislocations on a preferred slip system. The process will be combined with the misfit dislocation management to control threading dislocation density at the surface.
