20 mΩ, 750 V High-Power AlGaN/GaN Heterostructure Field-Effect Transistors on Si Substrate

Low on-resistance and high-breakdown-voltage AlGaN/GaN heterostructure field-effect transistors (HFETs) on Si substrate were fabricated. To improve the breakdown voltage of HFET, the total thickness of epitaxial layers was increased and the gate-to-drain spacing was expanded. As a result, the fabricated AlGaN/GaN HFETs with a gate width of 516 mm exhibited a breakdown voltage of 750 V, an on-resistance of 20 m?, and a maximum drain current of more than 170 A. The on-resistance?area product (Ron ?A) was 0.26 ??mm2. This value was approximately 1/30 compared with that of conventional Si metal?oxide?semiconductor field-effect transistors (MOSFETs).