Performance Enhancement of NiO<sub> <i>x</i> </sub>/β-Ga₂O₃ Heterojunction Diodes by Synergistic Interface Engineering
Dinghe Liu, Zeyulin Zhang, Hao Chen, Xusheng Tian, Yao Wang, Yiru Yan, Liru Zeng, Xinke Liu, Dazheng Chen, Qian Feng, Hong Zhou, Zhihong Liu, Jincheng Zhang, Chunfu Zhang, Yue Hao
Abstract
In this work, we report on achieving enhanced performance NiOx/beta gallium oxide (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula>-Ga2O3) heterojunction p-n diodes (HJDs) through synergistic interface engineering (SIE), which can greatly improve the electrical characteristics and interface characteristics of HJDs. It is shown that the NiOx surface undergoes morphological improvement and hole concentration enhancement after the UV/ozone treatment (UVO). Owing to the improved interfacial properties of Ni/NiOx, the forward conduction current of NiOx/<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula>-Ga2O3 HJD has significantly increased. Furthermore, the HJD performance can be improved by SIE with UVO and postannealing, especially for the reverse breakdown characteristics. Finally, a high-performance HJD without any terminal structure is obtained, which exhibits a low specific on-resistance of 2.47 m<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Omega \cdot $ </tex-math></inline-formula>cm2 and a high breakdown voltage of 1355 V, yielding a high Baliga’s figure of merit (BFOM) of 0.743 GW/cm2, which is a 219.17% enhancement in performance compared to untreated device. This work offers a practical and effective strategy for developing advanced Ga2O3 devices with exceptional performance metrics, paving the way for future technological breakthroughs.