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A Physics-Based Approach to Model Hot-Electron Trapping Kinetics in p-GaN HEMTs
Abstract
Hot electron trapping can significantly modify the performance of GaN-based HEMTs during hard switching operation. In this letter, we present a physics-based model based on rate equations to model the trapping kinetics of hot-electrons in GaN transistors submitted to semi- ON-state stress. The model is validated through comparison with the experimental data, obtained by means of a pulsed-drain current transient setup developed ad-hoc. Hot-electron trapping is found to have logarithmic time dependence; the first 10 μs of operation are critical in determining the current collapse during stress.
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During OFF-state operation, high drain voltages can lead to injection of electrons into surface states and/or buffer traps in GaN HEMTs.
“during OFF-state operation the transistor is subjected to very high drain voltages that can lead to the injection of electrons into surface states [32] and/or in buffer traps [33]”
From Review and Outlook on GaN and SiC Power Devices: Industrial State-of-the-Art, Applications, and Perspectives (2024) · cites this paper as [32]
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Metadata
- Authors
- Modolo, N., De Santi, C., Minetto, A., Sayadi, L., Sicre, S., Prechtl, G., Meneghesso, G., Zanoni, E., & Meneghini, M.
- Affiliations
- University of Padua (IT)
- Graz University of Technology (AT)
- Infineon Technologies (Austria) (AT)
- ORCID
- Venue
- IEEE Electron Device Letters
- Published
- 2021-05
- Volume
- 42
- Issue
- 5
- Pages
- 673-676
- ISSN
- 0741-3106 (ISSN-L)
- 1558-0563
- OpenAlex
- W3139430276
- Cited by
- 48
- References
- 22
- Citations by year
- 2026: 4 · 2025: 7 · 2024: 12 · 2023: 12 · 2022: 7 · 2021: 6
- FWCI
- 3.89
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- IEEE Electron Device Letters (publishedVersion)
- CINECA IRIS Institutial research information system (University of Pisa) (submittedVersion)
- Padua Research Archive (University of Padova) (submittedVersion)
- Topics
- Physical Sciences › Physics and Astronomy › Condensed Matter Physics › GaN-based semiconductor devices and materials
- Physical Sciences › Engineering › Electrical and Electronic Engineering › Silicon Carbide Semiconductor Technologies
- Physical Sciences › Engineering › Electrical and Electronic Engineering › Advancements in Semiconductor Devices and Circuit Design
- Keywords
- hot electron trapping, p-GaN HEMT, trapping kinetics, rate equations, physics-based modeling, hard switching, current collapse, GaN transistors
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