A 28-GHz Low-Loss AlGaN/GaN HEMT for T X /R X Switches in 5G Base Stations

The efficiency and switching performance of a L G = 0.25 μm GaN-HEMT with an aluminium gallium nitride back barrier (BB) and discrete field plate is examined in this article. The discrete-field plate minimizes the gate capacitance, such as drain gate capacitance and source gate capacitance, owing to its minimal FP area. Moreover, the AlGaN BB suppresses the vertical leakage towards the SiC substrate. Therefore, a tremendous enhancement is achieved in device efficiency and its switching characteristics. The discrete field plated HEMT with AlGaN BB offers a very low ON resistance ( R ON ) and minimum gate capacitance ( C G ) of 32.5 Ω.mm and 975 fF/mm respectively. Besides, the switching loss ( E SW ) and switching delay ( D SW ) are greatly reduced using the proposed field plated HEMT with AlGaN BB. It exhibits an E SW and D SW of 24 pJ and 5.8 pS, respectively. Furthermore, the exhibited current gain cut-off frequency of the proposed HEMT is 28 × 10 9 Hz. Hence, the discrete field plated HEMT with AlGaN BB is an excellent device for 28-GHz T X /R X switches in a 5G base station.