Epitaxial high-K barrier AlBN/GaN HEMTs
We report a polarization-induced 2D electron gas (2DEG) at an epitaxial AlBN/GaN heterojunction grown on a SiC substrate. Using this 2DEG in a long conducting channel, we realize ultra-thin barrier AlBN/GaN high electron mobility transistors that exhibit current densities > 0.25 A/mm, clean current saturation, a low pinch-off voltage of −0.43 V, and a peak transconductance of ∼0.14 S/mm. Transistor performance in this preliminary realization is limited by the contact resistance. Capacitance–voltage measurements reveal that introducing ∼7% B in the epitaxial AlBN barrier on GaN boosts the relative dielectric constant of AlBN to ɛrAlBN∼16, higher than the AlN dielectric constant of ɛrAlN∼9. Epitaxial high-K barrier AlBN/GaN HEMTs can thus extend performance beyond the capabilities of current GaN transistors.
Authors
- David J. Smith (ORCID: https://orcid.org/0000-0002-8810-4386)
- Kazuki Nomoto
- Debdeep Jena (ORCID: https://orcid.org/0000-0002-4076-4625)
- Thai‐Son Nguyen (ORCID: https://orcid.org/0000-0002-1193-834X)
- Chandrashekhar Savant (ORCID: https://orcid.org/0000-0001-7174-1103)
- Huili Grace Xing (ORCID: https://orcid.org/0000-0002-2709-3839)
- Siyuan Ma
- Joseph Casamento (ORCID: https://orcid.org/0000-0002-8621-1145)
- Yu‐Hsin Chen (ORCID: https://orcid.org/0009-0003-1408-9210)
- Saurabh Vishwakarma (ORCID: https://orcid.org/0000-0003-3130-1984)
- A. K. Dhar (ORCID: https://orcid.org/0000-0003-4143-2849)
Institutions
- Cornell University (US)
- Arizona State University (US)
- Massachusetts Institute of Technology (US)
Publication Details
- Journal
- Applied Physics Letters
- Published
- 2025-03-01
- DOI
- https://doi.org/10.1063/5.0235294
- Citations
- 9
- Primary Topic
- GaN-based semiconductor devices and materials
- Type
- article
- Field-Weighted Citation Impact
- 11.32
Funders
- National Science Foundation
- U.S. Department of Energy
- Semiconductor Research Corporation
- Army Research Office