High quality dielectric‐semiconductor interfaces are critical for reliable high‐performance transistors. This paper reports the in situ metal–organic chemical vapor deposition of Al2O3on β‐Ga2O3as a potentially better alternative to the most commonly used atomic layer deposition (ALD). The growth of Al2O3is performed in the same reactor as Ga2O3using trimethylaluminum and O2as precursors without breaking the vacuum at a growth temperature of 600 °C. The fast and slow near interface traps at the Al2O3/β‐Ga2O3interface are identified and quantified using stressed capacitance–voltage (CV) measurements on metal oxide semiconductor capacitor (MOSCAP) structures. The density of shallow and deep level initially filled traps (Dit) are measured using ultraviolet‐assisted CV technique. The average Ditfor the MOSCAP is determined to be 6.4
Dry deposition, the second largest removal process of ozone (O3) in the troposphere, plays a role in controlling the natural variability of surface O3concentrations. Terrestrial ecosystems remove O3either through stomatal uptake or nonstomatal processes. In chemical transport models, nonstomatal pathways are roughly constrained and may not correctly capture total O3loss. To address this, the first simultaneous eddy covariance measurements of O3and formic acid (HCOOH), a tracer of in‐canopy oxidation of biogenic terpenes, were made in a mixed temperate forest in Northern Wisconsin. Daytime maximum O3deposition velocities,
- Award ID(s):
- 1822420
- NSF-PAR ID:
- 10384657
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 48
- Issue:
- 3
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract × 1011cm−2eV−1. The conduction band offset of the Al2O3/ Ga2O3interface is also determined from CV measurements and found out to be 1.7 eV which is in close agreement with the existing literature reports of ALD Al2O3/Ga2O3interface. The current–voltage characteristics are also analyzed and the average breakdown field is extracted to be approximately 5.8 MV cm−1. This in situ Al2O3dielectric on β‐Ga2O3with improved dielectric properties can enable Ga2O3‐based high‐performance devices. -
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