Demonstration of Ultra Low 2DEG Sheet Resistance Using Al-Enriched AlGaN Layer in the Al<sub>X</sub>Ga<sub>1-X</sub>N/AlN/GaN Heterojunction
Gallium Nitride (GaN) High Electron Mobility Transistors (HEMTs) based on a bi-dimensional electron gas (2DEG) are essential components in many electronic applications. A crucial aspect involves minimizing the sheet resistance of the 2DEG to reduce the total on-state resistance of the device. In this study, we explored AIGaN layers with high aluminum content ranging from 0.24 to 0.60. We report significantly low 2DEG sheet resistance of $213 \Omega / \square$ at $25^{\circ} \mathrm{C}$ and $455 \Omega / \square$ at $150^{\circ} \mathrm{C}$ for the $\mathrm{Al}_{0.6} \mathbf{G a}_{0.4} \mathrm{~N} / \mathrm{AIN} / \mathrm{GaN}$ heterojunction, induced by a higher electron density ($\mathrm{n}_{\mathrm{s}}$), and despite a decrease in mobility with higher aluminum content ($\mu_{2 \mathrm{DEG}}$). The increase of the 2DEG density with the highest aluminum molar concentration is explained by a reduced polarization charge at the $\mathrm{Al}_{\mathrm{x}} \mathrm{Ga}_{1-\mathrm{x}} \mathrm{N} / \mathrm{AIN}$ interface, and it is validated by 1D Poisson-Schrödinger simulations.
Authors
- A. Olivier (ORCID: https://orcid.org/0000-0002-4906-4377)
- S. Torrengo (ORCID: https://orcid.org/0000-0003-0014-7881)
- C. Piotrowicz
- B. Mohamad
- Nathalie Malbert
Institutions
- Centre National de la Recherche Scientifique (FR)
- Université de Bordeaux (FR)
- Commissariat à l'Énergie Atomique et aux Énergies Alternatives (FR)
- Laboratoire d'Électronique des Technologies de l'Information (FR)
- Laboratoire de l'Intégration du Matériau au Système (FR)
- Institut Polytechnique de Bordeaux (FR)
- Université Grenoble Alpes (FR)
Publication Details
- Published
- 2024-09-09
- DOI
- https://doi.org/10.1109/esserc62670.2024.10719578
- Primary Topic
- GaN-based semiconductor devices and materials
- Type
- article
- Field-Weighted Citation Impact
- 0.00