High Breakdown Voltage and Low-Current Dispersion in AlGaN/GaN HEMTs With High-Quality AlN Buffer Layer
- Resource Type
- Periodical
- Authors
- Kim, J.; Cho, C.; Kim, E.; Hwang, J.S.; Park, K.; Lee, J.
- Source
- IEEE Transactions on Electron Devices IEEE Trans. Electron Devices Electron Devices, IEEE Transactions on. 68(4):1513-1517 Apr, 2021
- Subject
- Components, Circuits, Devices and Systems
Engineered Materials, Dielectrics and Plasmas
Buffer layers
III-V semiconductor materials
Aluminum nitride
Gallium nitride
Wide band gap semiconductors
Aluminum gallium nitride
HEMTs
AlGaN/GaN
AlN Buffer
BV₂/RON
high electron mobility transistor (HEMT)
SP
- Language
- ISSN
- 0018-9383
1557-9646
We have successfully grown AlGaN/GaN high electron mobility transistor (HEMT) structure on the high-quality undoped thick AlN buffer layer with large band offset to replace the conventional high-resistivity GaN buffer layer. The AlGaN/GaN HEMT fabricated on this AlN buffer layer exhibits low OFF-state leakage current with high ${I}_{\mathrm{\scriptscriptstyle ON}}/{I}_{\mathrm{\scriptscriptstyle OFF}}$ of $\sim 10^{{6}}$ due to enhanced confinement of the electrons in the 2-D electron gas (2-DEG) channel. The undoped AlN buffer layer is responsible for suppressing the trapping effects to greatly reduce the current dispersion in pulsed ${I}_{\text {D}}$ – ${V}_{\text {D}}$ characteristics, which is hardly avoided in conventional deep acceptor-doped GaN buffer layer. The device also demonstrates high breakdown voltage of 2154 V with very high figure of merit (FOM) of ~1.8 GV $^{2-1}$ cm $^{-{2}}$ , one of the highest ever reported, suggesting that the AlGaN/GaN-based Hemts WITH AlN buffer layer are promising for high-performance RF and power applications.