Wafer bonding of
Direct wafer bonding of β-Ga2O3and N-polar GaN at a low temperature was achieved by acid treatment and atmospheric plasma activation. The β-Ga2O3/GaN surfaces were atomically bonded without any loss in crystalline quality at the interface. The impact of post-annealing temperature on the quality of bonding interfaces was investigated. Post-annealing at temperatures higher than 700 °C increases the area of voids at bonded interfaces probably due to the difference in the coefficient of thermal expansion. The integration of β-Ga2O3on the GaN substrate achieved in this work is one of the promising approaches to combine the material merits of both GaN and Ga2O3targeting the fabrication of novel GaN/β-Ga2O3high-frequency and high-power electronics as well as optoelectronic devices.
more » « less- NSF-PAR ID:
- 10364721
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 120
- Issue:
- 14
- ISSN:
- 0003-6951
- Page Range / eLocation ID:
- Article No. 142101
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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