Reverse Blocking Enhancement‐Mode AlGaN/GaN HEMTs with Hybrid p‐GaN Ohmic Drain on the Si Substrates

Abstract

Hybrid p‐GaN Ohmic drain reverse blocking high electron mobility transistors (RB‐HEMTs) and conventional p‐GaN Enhancement‐mode (E‐mode) HEMTs are designed and fabricated on the Si substrates. Compared with the conventional p‐GaN HEMT, the RB‐HEMT can achieve great reverse blocking capability. The forward and reverse blocking voltages of the RB‐HEMT are 1116 V and 1056 V and the turn‐on voltage of the device is 1.07 V. When the temperature rises from 25 °C to 150 °C, the turn‐on voltage of the RB‐HEMT increases from 1.07V to 1.10 V, and the Vth increases from 1.97V to 2.07 V. The difference in turn‐on voltage and threshold voltage is mainly due to the different metals in contact between the gate and drain electrodes and p‐GaN. The reverse leakage current of the RB‐HEMT is 1.16 × 10−1 mA mm−1 when the temperature is 150 °C, which still keep good reverse blocking ability at high temperatures.