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Vertical geometry NiO/β n-Ga2O/n+ Ga2O3 heterojunction rectifiers with contact sizes from 50 to 200 μm diameter showed breakdown voltages (VB) up to 7.5 kV for drift region carrier concentration of 8 × 1015 cm−3. This exceeds the unipolar 1D limit for SiC and was achieved without substrate thinning or annealing of the epi layer structure. The power figure-of-merit, VB2/RON, was 6.2 GW cm−2, where RON is the on-state resistance (9.3–14.7 mΩ cm2). The average electric field strength was 7.56 MV/cm, approaching the maximum for β-Ga2O3. The on–off ratio switching from 5 to 0 V was 2 × 1013, while it was 3 × 1010–2 × 1011 switching to 100 V. The turn-on voltage was in the range 1.9–2.1 V for the different contact diameters, while the reverse current density was in the range 2 × 10−8–2 × 10−9 A cm−2 at −100 V. The reverse recovery time was 21 ns, while the forward current density was >100 A/cm2 at 5 V.
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MICROCOLEUS AS TOXIC BENTHIC MATS ON DIFFERENT BOTTOM SUBSTRATES: ECOPHYSIOLOGY AND DISTRIBUTION
The growth of the toxic Genera Microcoleus on different bottom substrates was presented. The sampling was performed in the Virgin River of Zion's National Park.
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- Award ID(s):
- 2222322
- PAR ID:
- 10569356
- Publisher / Repository:
- 12th U.S. Symposium on Harmful Algae, Portland, Maine, USA
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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