Valence band offsets for CuI on (-201) bulk Ga2O3 and epitaxial (010) (Al0.14Ga0.86)2O3
Abstract
Thin films of copper iodide (CuI) were grown on (-201) bulk Ga2O3 and (010) epitaxial (Al0.14Ga0.86)2O3 using a copper film iodination reaction method. The valence band offsets for these heterostructures were measured by X-ray photoelectron spectroscopy (XPS). High resolution XPS data of the O 1s peak and onset of elastic losses were used to establish the (Al0.14Ga0.86)2O3 bandgap to be 5.0 ± 0.30 eV. The valence band offsets were −0.25 eV ± 0.07 eV and 0.05 ± 0.02 eV for CuI on Ga2O3 or (Al0.14Ga0.86)2O3, respectively. The respective conduction band offsets were 1.25 ± 0.25 eV for Ga2O3 and 1.85 ± 0.35 eV for (Al0.14Ga0.86)2O3. Thus, there is a transition from type-II to type-I alignment as Al is added to β-Ga2O3. The low valence band offsets are ideal for hole transport across the heterointerfaces.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Oct 29, 2018
- Source ID
- 10.1063/1.5055941
Entities
People
- B. P. Gila
- Chaker Fares
- David C. Hays
- Fan Ren
- Karl D. Hobart
- Marko J. Tadjer
- Stephen Pearton
Organizations
- Defense Threat Reduction Agency
- Office of Naval Research
- United States Naval Research Laboratory
- University of Florida