Square-Gate AlGaN/GaN HEMTs With Improved Trap-Related Characteristics

Abstract

In this brief, the trap-related characteristics of high-breakdown AlGaN/GaN high-electron-mobility transistors (HEMTs) were investigated. Compared with a conventional multifinger layout, the square-gate design presented reduced the current collapse from 19% to 6% and almost eliminated the gate lag. The flicker noise density and the gate leakage decreased from 1.16 x 10(-10) to 1.17 x 10(-11) 1/Hz (f = 100 Hz) and from 7.36 x 10(-5) to 1.80 x 10(-6) A/mm (V(GS) = -4 V and V(DS) = 100 V), respectively. The breakdown voltage was also improved from 350 to 650 V. With the channel area away from the defects generated by the mesa etching process, the square-gate AlGaN/GaN HEMTs demonstrated excellent performance with much less trapping effects.