Development of Aluminum Epilayers as Buffers for GaInAs

Aluminum could be used as a structural buffer and sacrificial layer that is lattice-matched on the (001) surface to GaInAs having a 45° in-plane rotation. Conventional MOCVD from trimethylaluminum results in nanocrystalline aluminum carbide. By using hydrogen-plasma assistance in the reactor inlet, we avoid carbide formation, allowing deposition of elemental aluminum. The microstructures of these films resulting from initial applications of this method are discussed.