High temperature characteristics of doped channel AlGaN/GaN MIS-HFETs with thin AlGaN barrier layer

The device performance of AlGaN/GaN-based metal-insulator-semiconductor heterostructure field effect transistors (MIS-HFETs) with a very thin AlGaN barrier and a heavily doped GaN channel for high 2DEG density has been investigated at elevated temperatures up to 250°C. The devices exhibited ultra-low gate current leakages under the reverse gate bias with very reasonable transconductance characteristics at both RT and high temperatures. MIS-HFETs with doped channel showed much higher saturation drain current and weaker current collapse than the conventional devices at RT and high temperatures.