Nanoscale Electrical Characterization of Organized GaAsP Nanowires for Photovoltaic Energy Harvesting

We report the characterization of GaAsP nanowires in view of their photovoltaic applications. The nanowires containing a p-i-n junction were elaborated by molecular beam epitaxy using Be and Si as p- and n- doping impurities. Electron beam induced current microscopy was used to analyze the electrical activity of single nanowires and of nanowire arrays. Nanowire array devices were fabricated by encapsulating the nanowires in a transparent polymer and contacting them with indium tin oxide electrode. Electron beam induced current microscopy in top view configuration is used to probe the electrical activity and homogeneity of the device. A Schottky barrier at the nanowire/ITO interface induced wire-to-wire inhomogeneity.