Improved RF power performance via electrostatic shielding effect using AlGaN/GaN/graded-AlGaN/GaN double-channel structure

The direct current and radio frequency of DCGC-HEMT and DCTB-HEMT were systematically investigated. Owing to the utilization of a graded-AlGaN bottom barrier to provide more carriers and shield traps in the buffer, DCGC-HEMT exhibited greater saturated drain current and suppression in drain lag, enabling it to show greater output performance than DCTB-HEMT. The improvement in the former’s superior large-signal characteristic indicates its potential for high-performance RF PA applications.