Improvement of Breakdown Characteristic for a Novel GaN HEMT with Enhanced Resistance Single-Event Transient Effect

A novel AlGaN/GaN high-electron mobility transistor (HEMT) is put forward to promote its breakdown characteristics and anti-single-event transient (SET) effect. The features of the proposed device are a hybrid GaN/AlN buffer layer and a uniform-groove high-k passivation layer between the gate and drain electrodes (HGKB-HEMT). First, the uniform-groove high-k passivation layer not only reduces the peak electric field at the gate edges, but also modulates the electric field distribution between the gate and drain. Therefore, the breakdown voltage (BV) and the anti-SET effect show a great improvement. Second, the buffer leakage current was effectively reduced by the hybrid buffer layer, resulting in a further increase in the BV. The BV of the HGKB-HEMT reached 1672 V, which is 82.7% higher than the conventional GaN HEMT, and the peak drain current induced by the SET effect of the HGKB-HEMT decreased by 60.7% at V_DS = 50 V. Moreover, the channel current of the HGKB-HEMT increased slightly and the on-state resistance decreased.