【Device Papers】Influence of Low-k/High-k Spacer Materials and Field Plate Engineering on the Breakdown Voltage of β-Ga₂O₃-Based LDMOSFETs

      Researchers from the Electronics and Communication Engineering National Institute of Technology Karnataka have published a dissertation titled "Influence of Low-k/High-k Spacer Materials and Field Plate Engineering on the Breakdown Voltage of β-Ga₂O₃-Based LDMOSFETs" in 2025 First International Conference on Intelligent Computing and Communication Systems (CICCS).

Abstract

      This work presents a high-performance trench-gate LDMOSFET based on β-gallium oxide (β-Ga₂O₃), an ultra-wide bandgap semiconductor renowned for its superior breakdown strength and availability of native substrates. The proposed design strategically combines geometric and material engineering to address the limitations of electric field concentration and voltage handling capability. Through calibrated TCAD simulations, the impact of extending the field plate length from 9 µm to 12 µm is evaluated in conjunction with different spacer dielectrics—low-κ SiO₂ and high-κ HfO₂. Results demonstrate a substantial enhancement in breakdown voltage (BV), with HfO₂-based devices achieving up to 4425 V, nearly doubling the performance of their SiO₂ counterparts. The high dielectric constant of HfO₂ enables superior lateral and vertical electric field redistribution, effectively mitigating peak field concentrations near the drain terminal. This synergy between high-κ dielectric and field plate engineering unlocks a scalable pathway for advancing β-Ga₂O₃ power devices toward next-generation high-voltage, high-efficiency switching applications.

DOI：

https://doi.org/10.1109/CICCS66437.2025.11280239