P-GaN-Gate GaN-on-Si HEMTs with BV>1200 V and Excellent Dynamic Performance Realized Through Low Power NH 3 Plasma Acceptor Re-Passivation

In this letter, we report p-GaN gate enhancement-mode (E-mode) GaN-on-Si high electron mobility transistors (HEMTs) fabricated using an Mg acceptor re-passivation technique (ARP HEMT) via NH₃plasma treatment. The gate-to-source and gate-to-drain access regions were subjected to hydrogen ion implantation through NH₃ plasma treatment in a plasma-enhanced chemical vapor deposition (PECVD) system, forming a high-resistance cap layer. The fabricated device demonstrates a high threshold voltage (VTH) of 2.1 V, a low gate reverse leakage current (Igr) of 10⁻¹¹A/mm, and a high ON/OFF current ratio (ION/IOFF) of up to 3×10⁹. The dynamic on-resistance (Ron,d) measured under a quiescent drain voltage (Vds,q) of 600 V with a stress time of 1200 s is only 1.03 times the static on-resistance (Ron,s) at 25°C. A breakdown voltage (BVOFF) of 1298 V and a specific on-resistance of 0.85 mΩ•cm2were achieved in a device with Lgd=6 μm after additional SiN passivation. The developed fabrication process shows significant potential for application in GaN-based power transistors.