High-Performance Integrated Dual-Gate AlGaN/GaN Enhancement-Mode Transistor

In this letter, we present a new AlGaN/GaN enhancement-mode (E-mode) transistor based on a dual-gate structure. The dual gate allows the transistor to combine an E-mode behavior with low on-resistance and very high breakdown voltage. The device utilizes an integrated gate structure with a short gate controlling the threshold voltage and a long gate supporting the high-voltage drop from the drain. Using this new dual-gate technology, AlGaN/GaN E-mode transistors grown on a Si substrate have demonstrated a high threshold voltage of 2.9 V with a maximum drain current of 434 mA/mm and a specific on-resistance of 4.3 m Ω·cm² at a breakdown voltage of 643 V.