A novel V-grooved vertical GaN-based HEMT on silicon utilizing 2DEG for enhanced performance

Abstract A GaN-on-Si vertical gallium nitride high-electron-mobility transistor that fully utilizes two-dimensional electron gas (2DEG) to conduct is proposed. The proposed structure is based on the anisotropic etching technique to form V-shaped grooves with (111)-oriented sidewalls on the Si substrate, on which an AlGaN/GaN heterostructure is grown to enable a vertical distribution of 2DEG, thereby significantly reducing the specific on-resistance and the energy loss per switching cycle. Compared to the GaN trench-gate MOSFET, and under the condition of identical threshold voltage ( V th ) and breakdown voltage, the proposed structure exhibits a specific on-resistance ( R on , sp ) of 0.16 m Ω ⋅ cm 2 and a single-cycle energy loss of 36.8 µ J at a switching frequency of 200 kHz, corresponding to reductions of 60.98% and 41.25%, respectively. The results indicate that the proposed structure has great potential for future high-power switching applications.