【Device Papers】1.36 kV Planar-gate Ga₂O₃ CAVET with Nitrogen-Graded Multi-Implanted Current Blocking Layer

      Researchers from Nanjing University and Suzhou Institute of Nano-Tech and Nano-Bionics have published a dissertation titled " 1.36 kV Planar-gate Ga₂O₃ CAVET with Nitrogen-Graded Multi-Implanted Current Blocking Layer " in ISPSD.

Abstract

      Vertical Ga₂O₃ power transistors have attracted significant interest for high-voltage applications; however, their performance is often compromised by process-induced defects, as conventional Ga₂O₃ transistors fabrication typically relies on plasma mesa and trench etching, which introduces sidewall damage, leakage paths, and premature breakdown. In this work, we report a normally-off planar-gate Ga₂O₃ CAVET fabricated using a fully ion-implanted and etch-free process flow, effectively eliminating plasma-induced damage and leading to a highly stable threshold voltage with ultra-low hysteresis. Furthermore, a nitrogen-graded current blocking layer (CBL) is realized through multi-step nitrogen ion implantations, forming a tailored vertical doping profile that efficiently suppresses off-state leakage and improves breakdown voltage (BV). As a result, the device achieves a high BV of 1.36 kV, an on-resistance (R_on) of 9.12 mΩ•cm², and a low hysteresis voltage of 116 mV. This work demonstrates that combining damage-free processing with graded CBL engineering provides an effective pathway toward high-performance and reliable vertical Ga₂O₃ power transistors.

DOI：

https://doi.org/10.1109/ISPSD64561.2026.11553968