Nitride surface chemistry influence on band offsets at epitaxial oxide/GaN interfaces
Abstract
GaN surface and near-surface chemistry influence on band offsets of oxide overlayers is demonstrated through X-ray photoelectron spectroscopy measurements using epitaxial (111)-oriented MgO films on (0001)-oriented Ga-polar GaN as a case study. For identical cleaning and MgO growth conditions, GaN subsurface oxygen impurities influence the GaN bare surface band bending and the ultimate band offset to MgO heterolayers. As the GaN surface oxygen concentration increases from an atomic concentration of 0.9% to 3.4%, the valence band offset to MgO decreases from 1.68 eV to 1.29 eV, respectively. This study highlights the sensitivity of the oxide/nitride interface electronic structure to GaN epilayer preparation and growth conditions.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 26, 2018
- Source ID
- 10.1063/1.5013605
Entities
People
- Andrew A. Allerman
- Barney L. Doyle
- Christina M. Rost
- Christopher T. Shelton
- Elizabeth A. Paisley
- James A. Ohlhausen
- Jon Ihlefeld
- Jon-Paul Maria
- Michael T. Brumbach
- Stanley Atcitty
- Zlatko Sitar
Organizations
- Army Research Office
- National Science Foundation
- North Carolina State University
- Sandia National Laboratories
- University of Virginia