[17p-P12-1~27] 13.7 Compound and power electron devices and process technology

[17p-P12-24] Normally-off operation of p-GaN gate AlGaN/GaN high electron mobility transistor

〇(M1)Yoshihiko Akazawa¹, Kondo Takaki¹, Shinya Yoshikawa¹, Naotaka Iwata¹, Hiroyuki Sakaki¹ (1.Toyota Tech Inst.)

Keywords:Normally off, GaN, HEMT

The high electron mobility transistor (HEMT) using the two dimensional electron gas of AlGaN/GaN heterojunction is suitable for applications such as microwave communication systems because it can operate at high speed with low on-resistance. However, the HEMT cannot normally shut off the drain current at the gate voltage of 0V. This is inappropriate from the viewpoint of cost reduction and fail-safe of the systems, and normally-off operation is required. In this study, an AlGaN/GaN HEMT using p-type GaN as a gate is studied without forming a gate recessed structure. Excellent device performances including a positive threshold voltage of 1.4 V as well as drain current of 330mA/mm were obtained. Also, the effect of the source resistance, which is related to the source-gate spacing, on device characteristics was recognized.