Abstract
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.
| Original language | English |
|---|---|
| Article number | 092105 |
| Journal | Applied Physics Letters |
| Volume | 121 |
| Issue number | 9 |
| DOIs | |
| State | Published - Aug 29 2022 |
Funding
This work was sponsored partly by the Army Research Office and was accomplished under Cooperative Agreement No. W911NF-19-2-0269. It was partly supported as part of ULTRA, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award No. DE-SC0021230, and in part by Rice\u2019s Technology Development Fund. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the Army Research Office or the U.S. Government. The U.S. Government is authorized to reproduce and distribute reprints for Government purposes notwithstanding any copyright notation herein. Focused ion beam (FIB) milling is performed at the Electron Microscopy Center (EMC) of Rice University and electron microscopy experiments are conducted as part of a user proposal at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. R.X. and H.Z. are supported by the U.S. National Science Foundation (NSF) under Award No. DMR 2005096. The authors would also like to thank the Thermo Fisher Scientific, Oregon USA, for help.