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 × 10 -10 to 1.17 × 10 -11 1/Hz (f = 100 Hz) and from 7.36 × 10 -5 to 1.80 × 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. © 2009 IEEE.