Temperature dependent high frequency performance of a 62% AlGaN channel HEMT

This article reports on the temperature dependent performance of a HEMT with an Al0.62Ga0.38N channel layer and an Al0.84Ga0.16N barrier layer grown by metal–organic chemical vapor deposition. The device in this report was measured at room temperature and elevated temperatures of 100–150 °C. The sheet resistance increased from 3.5 kΩ/sq (25 °C) to 5.4 kΩ/sq (150 °C), while the contact resistance remained nominally similar. For a device with 160 nm gate length and 2 μm source-to-drain length, excellent electrical characteristics have been achieved when the device was operated at 150 °C with a fT of 17 GHz and a fmax of 25.6 GHz. The reported device also exhibited outstanding gate leakage control, where 60% Al composition AlGaN channel HEMT, which suggests the great potential of AlGaN channel devices for high frequency, high power, high temperature applications.