[J-1] Advanced Technologies for GaN Devices

[J-1-03] Effect of Atomic Layer Etching using Nitrogen Plasma on Hall Accumulation at MIS Interface of GaN Polarization-Junction Substrate

〇Takuya Hoshii¹, Shonosuke Kimura¹, Kuniyuki Kakushima¹, Hitoshi Wakabayashi¹, Kazuo Tsutsui¹ (1. Tokyo Tech (Japan))

Presentation style: On-site (in-person)

https://doi.org/10.7567/SSDM.2022.J-1-03

Atomic layer etching (ALE) is a promising process for fabricating recessed-gate GaN devices with superior MIS interfaces. In this study, nitrogen-plasma ALE was applied for the p-channel GaN MISFETs, and the resulting drive current improvement was verified. This improvement indicates a contribution of hole accumulation at the MIS interface. Also, XPS for the MIS interfaces revealed that ALE using nitrogen plasma could reduce the Ga oxides, which would be attributed to the suppression of nitrogen desorption from GaN surfaces during etching and resulting in superior MIS properties. Therefore, nitrogen-plasma ALE could be a novel technique to improve the performance of p-channel GaN MISFETs.