Millimeter-wave AlGaN/GaN HEMT breakdown voltage enhancement by a recessed float field plate

Abstract

We propose an innovative recessed float field plate (RFFP) structure for millimeter-wave AlGaN/GaN high-electron-mobility transistors (HEMTs). The reduced peak electric field contributes to a three-terminal breakdown voltage of 122-140 V for RFFP GaN HEMTs with L GD = 1.35 μm, which is found to increase from 84 to 101 V. The current collapse characteristic is also improved significantly. No obvious increase in parasite capacitance is observed after integrating the novel RFFP, thereby maintaining the high-frequency performance of GaN HEMTs. This technique is especially attractive for HEMTs of millimeter-wave frequency and above, and has great potential for applications.