【Device Papers】Self-aligned SnO/β-Ga₂O₃ mesa heterojunction diodes with a PFOM of 0.93 GW/cm²

      Researchers from Hefei University of Technology have published a dissertation titled " Self-aligned SnO/β-Ga₂O₃ mesa heterojunction diodes with a PFOM of 0.93 GW/cm² " in Journal of Semiconductors.

Abstract

      In this article, a vertical SnO/β-Ga₂O₃ mesa heterojunction diode (mesa-HJD) fabricated through self-aligned etching is reported. The mesa structure eliminates the influence of lateral depletion at the region, leading to an improved breakdown characteristics in comparison with its unterminated heterojunction diode (UT-HJD) counterpart. The SnO/β-Ga₂O₃ mesa-HJD, featuring a 500 nm mesa depth, achieves a breakdown voltage (BV) of 1100 V, which can be improved to 1631 V by sidewall passivation. With the increase of mesa depth, BV increases, accompanied by the increase of specific on-resistance (R_on,sp). Therefore, a maximum Baliga’s power figure of merit (PFOM) can be achieved for the optimized device with 500 nm mesa depth, giving the value of 0.93 GW/cm² for the passivated device. The mesa-HJD demonstrates considerable potential for application in high BV β-Ga₂O₃ power electronic devices in the future.

DOI：

https://www.jos.ac.cn/en/article/doi/10.1088/1674-4926/26020066