Robab Madadi - graduate of Islamic Azad University, Arak, Iran
Saeid Marjani - Electrical Engineering Department of Ferdowsi University of Mashhad, Iran.
Rahim Faez - Electrical Engineering Department of Sharif University of Technology, Tehran, Iran;
Seyed Ebrahim Hosseini - Electrical Engineering Department of Ferdowsi University of Mashhad, Iran.

In this paper, the microwave noise of Al0.3Ga0.7N/GaN heterojunction high electron-mobility transistors (HEMTs) with three different structures is investigated by using TCAD extensive simulations. By inserting a 21 nm Al0.05Ga0.95N bottom barrier layer at 14 nm away from the AlGaN/GaN heterointerface, the device shows higher transconductance and lower minimum noise figure (NFmin) than conventional AlGaN/GaN HEMT. In order to further improve the device performance, a new AlGaN/GaN DC-HEMT structure is proposed by inserting a 3 nm In0.1Ga0.9N layer at 6 nm away from the Al0.05Ga0.95N/GaN heterointerface. Due to higher carrier density and mobility, AlGaN/GaN DC-HEMT with In0.1Ga0.9N shows higher transconductance and lower NFmin than Al0.3Ga0.7N/GaN DC- HEMT.

AlGaN/GaN, double channel (DC) HEMTs, InGaN, minimun noise figure (NFmin)