Nanoscale surface characterization of GaN nanowires correlated with metal contact characteristics

Abstract

AbstractSurface electronic properties of GaN nanowires have been investigated using scanning probe microscopy and correlated with metal/nanowire contact characteristics. Surface current map of the nanowire was observed to be highly nonuniform, resulting from a large variation in surface barrier of the nanowire, on the order of a few tenths of an eV. The surface barrier non‐uniformity, which most likely determines the formation of an ohmic or Schottky contact, is increased dramatically with the nanowire surface deformation. Current–voltage characteristics and scanning gate microscopy of the nanowires also indicate significant carrier trapping at the nanowire and silicon dioxide surface. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)