Over 1 GW/cm<sub>2</sub> Vertical Ga<sub>2</sub>O<sub>3</sub> Schottky Barrier Diodes Without Edge Termination
Qiming He, Weibing Hao, Xuanze Zhou, Yu Li, Kai Zhou, Chen Chen, Wenhao Xiong, Guangzhong Jian, Guangwei Xu, Xiaolong Zhao, Xiaojun Wu, Junfa Zhu, Shibing Long
Abstract
This work demonstrates vertical <inline-formula> <tex-math notation="LaTeX">$\boldsymbol {\beta } $ </tex-math></inline-formula>-Ga<sub>2</sub>O<sub>3</sub> Schottky barrier diodes (SBDs) breaking through the power figure of merit of 1 GW/cm<sup>2</sup> without edge termination. The unreliable surface on the top of <inline-formula> <tex-math notation="LaTeX">$\sim {1.2}\times {10} ^{{16}}$ </tex-math></inline-formula> cm<sup>−3</sup> drift region, which naturally formed in air, was removed by inductively coupled plasma etching. The repaired surface was exposed to ambient air for less than 10 minutes during the entire preparation process. Compared with the excessive air exposure samples, the leakage current was well suppressed for the Ni/ <inline-formula> <tex-math notation="LaTeX">$\boldsymbol {\beta } $ </tex-math></inline-formula>-Ga<sub>2</sub>O<sub>3</sub> SBDs fabricated on a clean surface. Moreover, the blocking voltage reaches a maximum value of 1720 V, and the forward/reverse characteristics of the diodes on the same wafer show good uniformity. These results pave the way for further improving the performance of <inline-formula> <tex-math notation="LaTeX">$\boldsymbol {\beta }$ </tex-math></inline-formula>-Ga<sub>2</sub>O<sub>3</sub> devices and verify the potential of <inline-formula> <tex-math notation="LaTeX">$\boldsymbol {\beta }$ </tex-math></inline-formula>-Ga<sub>2</sub>O<sub>3</sub> SBDs for power applications.