In-plane InAs nanowires with buffer and capping layers by molecular beam epitaxy selective area growth

Complex branched geometries of in-plane InAs nanowires prepared by selective area growth can be used as a scalable platform to realize and study quantum devices. Defects and disorder at the interface between InAs and the substrate as well as at the bare top surface are limiting factors that degrade the electrical properties of the nanowires. We studied selective area growth of InAs, GaAs, InGaAs, GaSb nanowires on InP(100) and InP(111) B substrates using molecular beam epitaxy. Highly insulating InGaAs and GaSb with lattice constant closely matched to InAs can be used as a buffer layer or a capping layer, which can reduce defects in InAs. The use of atomic hydrogen during growth enabled clean native oxide desorption and improved selectivity as well as quality of InGaAs nanowires. The improved selectivity and the change in the major facet planes as per the substrate orientation were observed by scanning electron micrograph. Further characterizations were carried out by using x-ray diffraction and atomic force microscopy. Electrical properties of InAs nanowires with and without buffer and capping layers will also be discussed.