High Performance Al0.10Ga0.90N Channel HEMTs

This letter reports the large maximum drain current AlGaN channel high-electron-mobility transistors (HEMTs) of 849 mA/mm with graded buffers and constant channel layer. The large drain current and the transconductance benefit from the high electronic mobility of 807 cm
²
/V · s and high saturated velocity. Furthermore, the device also shows a low off-state drain current of ~1 nA/mm and an ultrahigh ION/IOFF up to ~10
⁹
. To the best of the authors' knowledge, the electronic mobility, the maximum drain current, and ION/IOFF ratio all are the largest reported results ever achieved on the AlGaN channel HEMTs. These results not only drastically reduce the performance gaps between the AlGaN channel HEMT and the GaN channel HEMT in the maximum drain current, the maximum transconductance, and the electronic mobility, but also demonstrate better performances in the gate leakage current, the off-state drain current, ION/IOFF ratio, and the breakdown voltage.