Two-dimensional device simulation for radio frequency performance of AlGaN/GaN HEMT

In order to obtain better high frequency performance for GaN-based devices, we investigate the influence of the gate length L g , the gate-source space L gs , the gate-drain space L gd , and the thickness of barrier AlGaN on frequency performance of AlGaN/GaN high electron mobility transistors (HEMTs) using silvaco TCAD simulation. Besides, the importance of Ohmic contact resistance R c to current-gain cutoff frequency f T is also presented by our simulation. It presents that the f T increases dramatically with the decrease of L g and R c while L gd and L gs affect f T lightly. Meanwhile, the optimized thickness of AlGaN barrier layer is obtained in our structure.