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Abstract This letter reports the demonstration of lateral AlN Schottky barrier diodes (SBDs) on single-crystal AlN substrates by metalorganic CVD (MOCVD) with an ultra-low ideality factor (η) of 1.65, a high Schottky barrier height of 1.94 eV, a breakdown voltage (BV) of 640 V, and a record high normalizedBVby the anode-to-cathode distance. The device current was dominated by thermionic emission, while most previously reported AlN SBDs suffered from defect-induced current with higherη(>4). This work represents a significant step towards high-performance ultra-wide bandgap AlN-based high-voltage and high-power devices.
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High-voltage kV-class AlN metal-semiconductor field-effect transistors on single-crystal AlN substrates
Abstract This letter reports the demonstration and electrical characterization of high-voltage AlN metal-semiconductor field-effect transistors (MESFETs) on single-crystal AlN substrates. Compared with AlN MESFETs on foreign substrates, the AlN-on-AlN MESFETs showed high breakdown voltages of over 2 kV for drain-to-gate spacing of 15 μm and one of the highest average breakdown fields among reported AlN MESFETs. Additionally, the devices also exhibited decent drain saturation current and on/off ratio without complicated regrown or graded contact layers, which are several times higher than those of reported AlN-on-sapphire MESEFTs. This work is beneficial for the future development of ultrawide bandgap AlN power electronics.
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- Award ID(s):
- 2338604
- PAR ID:
- 10552729
- Publisher / Repository:
- DOI PREFIX: 10.35848
- Date Published:
- Journal Name:
- Applied Physics Express
- Volume:
- 17
- Issue:
- 10
- ISSN:
- 1882-0778
- Format(s):
- Medium: X Size: Article No. 104002
- Size(s):
- Article No. 104002
- Sponsoring Org:
- National Science Foundation
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