We demonstrate that MOCVD growth of AlGaN on GaN via facet controlled epitaxial lateral overgrowth (FACELO) allows for the growth of thick, relaxed, doped, c-oriented layers. The process includes patterning of the substrate, growth of GaN with pyramidal planes, and epitaxy of AlGaN. We show that AlGaN films with 30% Al-content and several microns of thickness can be grown. The fully coalesced films have a clean, crack free surface with an AFM RMS of 1 nm in a 10x10 μm2 area. Dislocation density is investigated via XRD and etch-pit-density and a dislocation density ranging 106 – 108 cm-2 is measured.
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