Impact of a nickel metal region in the buried oxide layer on SOI-MESFET performance: A simulation study

• Nickel region boosts SOI-MESFET breakdown voltage by 67.5% to 26.5 V. • New design reduces electric field congestion via Ni layer and gate shift. • Power density rises 126% in proposed SOI-MESFET vs. conventional. • RF performance improves with fmax reaching 114.8 GHz in new structure. • Atlas 2D simulation validates enhanced transconductance and charge control. This paper investigates the electrical properties of a 0.3 µm channel length Silicon-On-Insulator (SOI) Metal-Semiconductor Field-Effect Transistor (MESFET) with a nickel (Ni) metal region in the buried oxide layer. The simulation was conducted using the ATLAS 2D device simulator from SILVACO. The effects of the proposed structure on the carrier concentration, threshold voltage, transconductance, and impact ionization rate are discussed in detail. It was found that the presence of the nickel metal region acts as a trap for charge carriers, reducing the impact ionization rate and modifying the electric field distribution. This leads to a significant improvement in the breakdown voltage (V_BR) from 16 V to 26.5 V, and an increase in the maximum oscillation frequency (f_max) from 85.5 GHz to 114.8 GHz compared to the conventional structure. Additionally, the proposed structure enhances the drain current, leading to a 126% increase in maximum output power density (P_max). The results demonstrate that the proposed SOI-MESFET is a promising candidate for high-frequency and high-power radio frequency (RF) amplifier applications.