Demonstration of 4.7 kV breakdown voltage in NiO/ β -Ga2O3 vertical rectifiers
Abstract
Vertical heterojunction NiO/β n-Ga2O/n+ Ga2O3 rectifiers employing NiO layer extension beyond the rectifying contact for edge termination exhibit breakdown voltages (VB) up to 4.7 kV with a power figure-of-merits, VB2/RON of 2 GW·cm−2, where RON is the on-state resistance (11.3 mΩ cm2). Conventional rectifiers fabricated on the same wafers without NiO showed VB values of 840 V and a power figure-of-merit of 0.11 GW cm−2. Optimization of the design of the two-layer NiO doping and thickness and also the extension beyond the rectifying contact by TCAD showed that the peak electric field at the edge of the rectifying contact could be significantly reduced. The leakage current density before breakdown was 144 mA/cm2, the forward current density was 0.8 kA/cm2 at 12 V, and the turn-on voltage was in the range of 2.2–2.4 V compared to 0.8 V without NiO. Transmission electron microscopy showed sharp interfaces between NiO and epitaxial Ga2O3 and a small amount of disorder from the sputtering process.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 25, 2022
- Source ID
- 10.1063/5.0097564
Entities
People
- Chao-Ching Chiang
- Fan Ren
- Honggyu Kim
- Jian-Sian Li
- Stephen Pearton
- Timothy Jinsoo Yoo
- Xinyi Xia
Organizations
- Defense Threat Reduction Agency
- National Science Foundation
- University of Florida