Supercritical Chemical Fluid Deposition of InP and InAs

Supercritical chemical fluid deposition (SCFD) from [(Bu2In)-Bu-n(mu-E'Bu-2)(2)(InBu2)-Bu-n] precursors (E = P or As) dissolved in a homogeneous hexane/CO2 fluid results in the growth of a thin film of InP or InAs with a thick mat of nanowires attached to the surface. InP films were well-adhered to the substrate and the nanowires can be removed without disrupting the film; however, the InAs films were poorly adhered, being dislodged simply by tapping the substrate. In many cases, the InP nanowires are single crystalline, and both the nanowires and the underlying films exhibit band-edge luminescence. Use of supercritical CHF3 as the delivery solvent also leads to good quality InP films and reduced carbon incorporation into the films. The single-source precursor system was responsible for significant amounts of carbon. This work shows that the SCFD method may be generally applicable to the growth of compound semiconductors, with important implications for growth of these materials in confined environments.