Oxygen Ion Implantation Isolation Planar Process for AlGaN/GaN HEMTs

Nat. Chiao Tung Univ., Hsinchu
IEEE Electron Device Letters (Impact Factor: 2.79). 07/2007; DOI: 10.1109/LED.2007.896904
Source: IEEE Xplore

ABSTRACT A multienergy oxygen ion implantation process was demonstrated to be compatible with the processing of high- power microwave AlGaN/GaN high electron mobility transistors (HEMTs). HEMTs that are isolated by this process exhibited gate-lag- and drain-lag-free operation. A maximum output power density of 5.3 W/mm at Vgs = -4 V and Vds = 50 V and a maximum power added efficiency of 51.5% at Vgs = -4 V and Vds = 30 V at 3 GHz were demonstrated on HEMTs without field plates on sapphire substrate. This isolation process results in planar HEMTs, circumventing potential problems with enhanced gate leakage due to the gate contacting the 2-D electron gas at the mesa sidewall.

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