Du, Y., Yan, H., Luo, P. et al. (5 more authors) (2023) Investigation on shift in threshold voltages of 1.2 kV GaN polarization superjunction (PSJ) HFETs. IEEE Transactions on Electron Devices, 70 (1). pp. 178-184. ISSN 0018-9383
Abstract
Shift in threshold voltages ( Vth ) of 1.2 kV P-GaN ohmic-gate normally- ON polarization superjunction (PSJ) HFETs is reported for the first time. Pulsed-mode measurement results of threshold voltage shifts under different gate stress biases are presented. A comprehensive analysis of threshold voltage shifts under different gate stress voltages and temperatures is discussed. Under positive gate stress voltages, hole trapping and accumulation processes in the u-GaN/AlGaN hetero-interface or the AlGaN layer induce more electrons, thereby causing negative shifts in threshold voltages. Conversely, under negative gate stress voltages, electrons captured by the buffer traps located in the GaN buffer or the traps in the AlGaN layer cause positive shifts in threshold voltages. Moreover, recovery processes are observed under the positive and negative stress voltages. Temperature effects on the Vth are also evaluated through pulsed-mode measurements. Hole trapping processes are strengthened with temperature rise, causing more negative Vth shifts. However, thermally activated electrons from 2DEG and strengthened recovery processes result in positive Vth shifts at higher temperatures, compensating the influences from the increasing hole trapping processes. The results confirm that the current collapse is quite low in PSJ HFETs
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. Reproduced in accordance with the publisher's self-archiving policy. |
Keywords: | GaN ohmic gate; gate stress; holes injection; polarization superjunction (PSJ); power devices; threshold voltages shift |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Engineering (Sheffield) > Department of Electronic and Electrical Engineering (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 07 Dec 2022 14:48 |
Last Modified: | 07 Dec 2023 01:13 |
Status: | Published |
Publisher: | Institute of Electrical and Electronics Engineers |
Refereed: | Yes |
Identification Number: | 10.1109/TED.2022.3225695 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:193820 |