AlGaN/GaN power HEMT devices for future energy conversion applications

The AlGaN/GaN high electron mobility transistor (HEMT) has drawn great interest in high power and high frequency applications owing to its outstanding material advantages, such as large critical electric field, high electron saturation velocity and the ability to form the high-density two dimensional electron gas (2DEG) conduction channel at the hetero interface. In this paper, a topical review on the device features is made, namely on its polarisation effects that lead to 2DEG formation at the AlGaN/GaN heterojunction, the surface field plate influence and the trap charges induced current collapse phenomenon during pulse operations. These effects are very important in understanding the AlGaN/GaN power HEMT devices.