A triple-oxide SOI-MESFET with enhanced breakdown voltage and power density via buried aluminum engineering

• Novel SOI-MESFET design with three oxide regions in the channel enhances breakdown voltage from 17 V to 24 V. • Aluminum layer in buried oxide (BOX) improves maximum power density from 0.000288 W/mm² to 0.000411 W/mm². • Reduced gate-source and gate-drain parasitic capacitances enhance RF performance, including higher transition frequency (fT). • Improved electric field distribution and thermal stability ensure suitability for high-power and high-frequency applications. • Validated through Silvaco ATLAS TCAD simulations, showing close agreement with experimental data. This study presents a novel triple-oxide SOI-MESFET structure with an engineered aluminum layer in the buried oxide (BOX) to simultaneously enhance breakdown voltage and power density. Through advanced TCAD simulations, we demonstrate a 44% increase in breakdown voltage (from 17V to 24V) and 41.00% higher maximum power density (0.739 W/mm vs 0.524 W/mm) compared to conventional designs. The strategic placement of three oxide regions in the channel optimizes electric field distribution, while the Al-BOX layer reduces parasitic capacitance and improves thermal stability. The device also exhibits excellent thermal stability, maintaining operation at ambient temperature under high bias conditions.