Design and Simulation of α-Ga₂O₃ Lateral Schottky Barrier Diodes with Field Plate Structure

Ga203 is considered to be an excellent material for fabricating high-voltage tolerant power devices due to its ultra-wide bandwidth. A high-voltage tolerant lateral <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\alpha-\text{Ga}_{2}\mathrm{O}_{3}$</tex> Schottky diode (SBD) with a reverse breakdown voltage (VBR) of 1826 V has been simulated by incorporating a field plate structure with a 7 um field plate (FP) and a 500 nm <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{SiO}_{2}$</tex> oxide layer. The parameters affecting the voltage withstand characteristics are analyzed, and the length of the FP, the thickness of the oxide layer and the material are investigated. As the LFP increases, the VBR increases towards saturation. This is attributed to the shift of the peak E-field towards the edge of the field plate. In addition, the increase in VBR is attributed to the ability of materials with thicker oxide layers and higher dielectric constants to support the E-field. This enhancement drives the E-field to concentrate at the edges of the FP and Schottky contact regions. These results suggest that lateral <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\alpha-\text{Ga}_{2}\mathrm{O}_{3}$</tex> SBDs have great potential for future power electronics applications.