Electroluminescence under the gate region using AlGaN/GaN HEMT with a transparent gate electrode

Abstract

AlGaN/GaN high electron mobility transistors with a transparent gate electrode are studied by means of electroluminescence (EL) to investigate under the gate region. We successfully observed EL emissions under the gate at off-state conditions and the gate edge at on-state conditions. We believe the EL through the transparent gate electrode is contributed to gate leakage path. Hence, this transparent gate technology is useful for future evaluation of localized gate leakage paths.

Improved hysteresis in a normally-off AlGaN/GaN MOS heterojunction field-effect transistor with a recessed gate structure formed by selective regrowth

“…A possible resolution for this issue is a selective area regrowth technique, which enables the formation of a recessed gate structure without dry etching. Although the AlGaN=GaN HFETs fabricated by this technique were reported, 6,7) its impact on the MOS interface was not clarified. Recently, we have applied the technique to an AlGaN=GaN MOS-HFET, which resulted in a normally-off operation with an improvement in hysteresis.…”