Abstract
The valence band offset (VBO) at the wurtzite-type, nitrogen-polarity InNAlN (000 1-) heterojunction has been determined by photoelectron spectroscopy to be 3.10±0.04 eV. The heterojunction samples used for this study have an atomically abrupt 8:9 commensurate interface, at which every eight-unit cell of InN aligns exactly with every nine-unit cell of AlN. The commensurately matched InNAlN heterojunction system grown on Si(111) is particularly suitable for the determination of VBO since both InN and AlN epitaxial layers are completely relaxed and the strain-induced piezoelectric fields, which are difficult to be quantitatively determined, have a negligible effect. © 2006 American Institute of Physics.