【Device Papers】5 kV NiO/β-Ga₂O₃ heterojunction diodes with dual-layer spatially modulated JTE and ± 79% process tolerance

      Researchers from Chongqing University of Technology have published a dissertation titled " 5 kV NiO/β-Ga₂O₃ heterojunction diodes with dual-layer spatially modulated JTE and ±79% process tolerance " in Microelectronics Journal.

Abstract

      A dual-layer spatially modulated junction termination extension (SM-JTE) was proposed for high-voltage beta-gallium oxide (β-Ga₂O₃) diodes. The structure comprises two SM-JTE layers, each containing a JTE body and nickel oxide (NiO) rings with varied widths and inter-ring spacings. The upper layer mitigates electric field crowding at the anode edge, whereas the lower layer promotes lateral field expansion, thereby enabling synergistic electric field modulation. This modulation broadens the D_JTE process window compared with conventional p-NiO JTE. Based on TCAD simulations, the ring dimensions and charge partition ratio between the two layers were optimized. For a 5 kV blocking target, the relative doping window (RDW) was expanded to ±79%, and a maximum breakdown voltage (V_BR) of 5.6 kV was achieved. The device also achieved a specific on-resistance (R_ON,SP) of 4.87 mΩ·cm² and a power figure of merit (PFOM) of 6.44 GW/cm². The proposed dual-layer SM-JTE provides a design approach for β-Ga₂O₃ power diodes combining high V_BR with a wide process window.

DOI：

https://doi.org/10.1016/j.mejo.2026.107346