DC, RF and noise figure analysis of p+ In0.2Ga0.8N cap gate AlGaN DH-HEMT

In this paper, to implement the normally-OFF HEMTs with a high threshold voltage (Vt) AlGaN HEMTs with a P+ InGaN cap layer is proposed. By polarization induced field in the InGaN cap layer, the conduction band is raised with a high Vt and a maximum Ion and much reduced I
off
for the device with a 1.4-μm long gate. A P + type InGaN gate transistor with AlGaN back-barrier/buffer can demonstrate the potential of DH-HEMTs with P+ InGaN cap for high voltage switching and microwave power applications.