Herein, a device study using technology computer‐aided design simulation to theoretically analyze the electrical performance of ultrawide‐bandgap boron nitride (BN)‐based vertical junction devices is performed, including h‐BN Schottky diode, h‐BN pn diode, and h‐BN/AlN pn diode; this is also the first demonstration of the BN power devices in simulation. The material properties of BN are defined with recently reported data, and the physical mechanisms of the device performance are systematically investigated. The h‐BN junctions in this simulation shows excellent performance, especially for breakdown behaviors. Schottky diode shows a turn‐on voltage of 0.6 V for Pt Schottky contact and breakdown voltages over 450 V for 5 μm, 6 × 1015 cm−3p‐type‐doped drift layer; The h‐BN pn diode shows a turn‐on voltage of 6 V and breakdown voltages over 3 kV with a critical electric field of 13.6 MV cm−1for 2.5 μm, 2 × 1016 cm−3p‐type‐doped drift layer. The h‐BN/AlN heterojunction pn diode shows a turn‐on voltage of 5.8 V and breakdown voltage over 2 kV for 2.5 μm, 2 × 1016 cm−3n‐type‐doped AlN drift layer. Herein, an understanding of the device principles of vertical BN junctions is provided, which can serve as a reference for the future development of robust BN power electronics.
Wide and ultrawide-bandgap semiconductors lie at the heart of next-generation high-power, high-frequency electronics. Here, we report the growth of ultrawide-bandgap boron nitride (BN) thin films on wide-bandgap gallium nitride (GaN) by pulsed laser deposition. Comprehensive spectroscopic (core level and valence band x-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, and Raman) and microscopic (atomic force microscopy and scanning transmission electron microscopy) characterizations confirm the growth of BN thin films on GaN. Optically, we observed that the BN/GaN heterostructure is second-harmonic generation active. Moreover, we fabricated the BN/GaN heterostructure-based Schottky diode that demonstrates rectifying characteristics, lower turn-on voltage, and an improved breakdown capability (∼234 V) as compared to GaN (∼168 V), owing to the higher breakdown electrical field of BN. Our approach is an early step toward bridging the gap between wide and ultrawide-bandgap materials for potential optoelectronics as well as next-generation high-power electronics.
more » « less- Award ID(s):
- 2005096
- NSF-PAR ID:
- 10439984
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 121
- Issue:
- 9
- ISSN:
- 0003-6951
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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