【Device Papers】Simulation Study of Enhancement-Mode β-Ga₂O₃ MOSFETs on a Novel P-Ga₂O₃/AlN/SiC Substrate

      Researchers from School of Science Yanshan University and Chongqing University of Posts and Telecommunication have published a dissertation titled " Simulation Study of Enhancement-Mode β-Ga₂O₃ MOSFETs on a Novel P-Ga₂O₃/AlN/SiC Substrate " in Micromachines.

Abstract

      This work presents the design of β-Ga₂O₃ MOSFET incorporating a P-type Ga₂O₃ buffer layer on a high-thermal-conductivity AlN/SiC composite substrate. The electrical characteristics of the device were simulated using Sentaurus TCAD. Results demonstrate that the integration of the composite substrate effectively mitigates self-heating effects, reducing the peak temperature (T_max) from 776.5 K to 570.9 K at 300 K, while simultaneously increasing the threshold voltage(V_th) from −0.35 V to 1.52 V. Through systematic optimization of the P-Ga₂O₃ buffer layer thickness and doping concentration, the device achieves a breakdown voltage(V_br) of 4781 V, a power figure of merit (PFOM) of 2.18 GW/cm², an I_DS, on/off ratio of 9.20 × 10⁹, and cut-off/maximum oscillation frequencies(f_t/f_max) of 1.29 GHz and 1.40 GHz, respectively. These findings provide a theoretical foundation for developing β-Ga₂O₃-based power devices with high breakdown voltage, improved thermal conductivity, and low specific on-resistance(R_on,sp).

DOI：

https://doi.org/10.3390/mi17050595