High performance normally-off recessed-gate GaN-based MIS-HEMTs achieved by oxygen plasma treatment

• Published in: 2023 IEEE International Meeting for Future of Electron Devices, Kansai (IMFEDK) pp. 1 - 2
• Main Authors: Ishiguro, M., Terai, S., Sekiyama, K., Urano, S., Baratov, A., Asubar, J. T., Kuzuhara, M.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 16-11-2023
• Subjects: enhancement-mode; GaN MIS-HEMT; Interface states; Oxygen; Oxygen plasma treatment; Performance evaluation; Plasmas; Scattering; Threshold voltage; Wide band gap semiconductors
• ISSN: 2836-9947
• DOI: 10.1109/IMFEDK60983.2023.10366337

We report on the high performance normally-off recessed-gate GaN-based MIS-HEMTs exhibiting excellent combination of maximum drain current (>600 mA/mm) and high positive threshold voltage (+1.3 V) achieved by oxygen plasma treatment. Using the positive threshold voltage shift phenomena previously demonstrated in oxygen plasma treated planar MIS-HEMTs, we were able to achieve robust enhancement-mode operation employing a relatively thick 9-nm-AlGaN barrier layer in the channel region. The rather thick AlGaN barrier may have suppressed remote scattering from insulator/AlGaN interface states leading, to high maximum drain current.