High-Temperature Sensitivity of a Depletion-Mode AlGaN/GaN MIS-HEMT

This article reports on the high-temperature (HT) operation (25 °C-400 °C) and temperature sensing mechanism of a depletion-mode AlGaN/GaN metal-insulator-semiconductor (MIS) high-electron-mobility transistor (depletion mode (D-mode) AlGaN/GaN MIS-HEMT) in GaN on Si technology. Our measurements and simulations show that the high sensitivity of the device is governed by traps at the GaN-cap/Si3N4 interface and in the GaN buffer layer. At subthreshold operation, the device temperature sensitivity reaches 8.73%/K at a drain-to-source current ( ${I}_{\mathrm{DS}}$ ) of 10 $\mu \text{A}$ /mm. This is similar to the values reported for silicon devices, but in a much wider temperature range and at much higher current densities.