Transport and trap states in proton irradiated ultra-thick κ-Ga2O3
Abstract
Changes induced by irradiation with 1.1 MeV protons in the transport properties and deep trap spectra of thick (>80 μm) undoped κ-Ga2O3 layers grown on sapphire are reported. Prior to irradiation, the films had a donor concentration of ∼1015 cm−3, with the two dominant donors having ionization energies of 0.25 and 0.15 eV, respectively. The main electron traps were located at Ec−0.7 eV. Deep acceptor spectra measured by capacitance-voltage profiling under illumination showed optical ionization thresholds near 2, 2.8, and 3.4 eV. The diffusion length of nonequilibrium charge carriers for ɛ-Ga2O3 was 70 ± 5 nm prior to irradiation. After irradiation with 1.1 MeV protons to a fluence of 1014 cm−2, there was total depletion of mobile charge carriers in the top 4.5 μm of the film, close to the estimated proton range. The carrier removal rate was 10–20 cm−1, a factor of 5–10 lower than in β-Ga2O3, while the concentration of deep acceptors in the lower half of the bandgap and the diffusion length showed no significant change.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Apr 27, 2023
- Source ID
- 10.1116/6.0002673
Entities
People
- A. Y. Polyakov
- A.A. Vasil'ev
- Eugene Yakimov
- I. Shchemerov
- In‐Hwan Lee
- Stephen Pearton
- А. I. Kochkova
- А. В. Черных
- А. И. Печников
- В. И. Николаев
- П. Б. Лагов
Organizations
- Defense Threat Reduction Agency
- Korea University
- Ministry of Science and Higher Education
- National Science Foundation
- National University of Science and Technology
- Russian Academy of Sciences
- University of Florida