Experimental Characterization of Impact Ionization and Projection of Critical Electric Fields in High‐Al Content AlGaN
Electron and hole impact ionization coefficients are obtained from measurements of high‐Al content Al x Ga 1‐ x N p–n diodes grown on AlN substrates. The photomultiplication method using a 193 nm pulsed laser is applied to measure the multiplication factor. The impact ionization coefficients are modeled using Chynoweth's formulation, based on electric field profiles determined from the solution of Poisson's equation. A least‐squares fit of the theoretical multiplication factor to the measured multiplication factor yields the impact ionization coefficients and the extracted electron impact ionization coefficients are consistent with previous numerical predictions. Furthermore, the theoretical breakdown voltage and critical electric field are computed based on the extracted impact ionization coefficients. These results provide much‐needed data to further optimize the design of optoelectronic, power switching, and high‐power RF devices based on ultrawide bandgap AlGaN.
Authors
- Pramod Reddy (ORCID: https://orcid.org/0000-0002-8556-1178)
- Patrick Fay (ORCID: https://orcid.org/0000-0003-1239-4978)
- Spyridon Pavlidis (ORCID: https://orcid.org/0000-0002-1690-2581)
- Yu‐En Jeng
- Seiji Mita (ORCID: https://orcid.org/0009-0002-8312-107X)
- Ronny Kirste (ORCID: https://orcid.org/0000-0002-2596-4450)
- Zhongtao Zhu (ORCID: https://orcid.org/0009-0009-6160-3685)
- Anthony J. Hoffman (ORCID: https://orcid.org/0000-0002-2166-8830)
- Yashas Satapathy (ORCID: https://orcid.org/0000-0002-9859-2838)
- Will Mecouch (ORCID: https://orcid.org/0000-0002-8317-5812)
- Zlatko Sitar (ORCID: https://orcid.org/0000-0002-7385-0837)
- Jaime A. Collazo (ORCID: https://orcid.org/0000-0002-1816-7744)
- Lina Cao (ORCID: https://orcid.org/0000-0003-3949-0513)
- Mauricio Gutierrez (ORCID: https://orcid.org/0000-0003-4313-7771)
- Juncheng Xiong (ORCID: https://orcid.org/0000-0002-6936-9127)
- Yu Duan (ORCID: https://orcid.org/0009-0006-3133-403X)
- Wesley Turner (ORCID: https://orcid.org/0009-0000-6540-0126)
Institutions
- University of Notre Dame (US)
- North Carolina State University (US)
- Adroit Materials (United States) (US)
Publication Details
- Journal
- physica status solidi (a)
- Published
- 2025-06-24
- DOI
- https://doi.org/10.1002/pssa.202500129
- Primary Topic
- GaN-based semiconductor devices and materials
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Science Foundation
- Division of Electrical, Communications and Cyber Systems
- Army Research Office