Properties and device performance of BN thin films grown on GaN by pulsed laser deposition

TL;DR

This study demonstrates the successful growth and characterization of ultrawide-bandgap BN thin films on GaN, revealing their potential for high-power electronics and optoelectronic applications due to improved electrical and optical properties.

Contribution

It introduces a pulsed laser deposition method for BN on GaN and provides comprehensive analysis of the resulting heterostructure's properties and device performance.

Findings

BN thin films grown on GaN confirmed by spectroscopy and microscopy

BN/GaN heterostructure exhibits second-harmonic generation activity

Schottky diode with BN/GaN shows lower turn-on voltage and higher breakdown voltage

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 XPS, FTIR, Raman) and microscopic (AFM and STEM) characterizations confirm the growth of BN thin films on GaN. Optically, we observed that 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 towards bridging the gap between wide and ultrawide-bandgap materials for potential optoelectronics as well as next-generation high-power electronics.