Valence-Band Discontinuity at the AlN/Si Interface

Abstract

The major problems of GaN-based light-emitting diodes on Si are their high series resistances and high operating voltages due to the large band discontinuity at the AlN/Si interface. We have observed the valence-band discontinuity at the AlN/Si interface using X-ray photoelectron spectroscopy (XPS). The valence- and conduction-band discontinuity values at the AlN/Si interface were found to be 2.8±0.4 eV and 2.3±0.4 eV, respectively.