Abstract
We conducted DC and small-signal RF characterization on AlGaN/GaN high-electron-mobility transistors (HEMTs) over a range of temperatures to examine temperature-dependent variations in key device performance metrics including transconductance (gm), extrinsic cutoff frequency (fT), maximum gain frequency (fmax), unilateral power gain (UPG), and maximum stable gain (MSG). Our findings indicate that device parameters decline with increasing temperature at a distinct rate. Specifically, a 100°C rise results in fT and fmax dropping by about 8 GHz and 17 GHz, respectively, while MSG decreases by approximately 1 dB. These changes are inherent to the device physics and are not influenced by its geometry or operational mode.
