Design optimization of high breakdown voltage AlGaN-GaN power HEMT on an insulating substrate for R/sub ON/A-V/sub B/ tradeoff characteristics

High breakdown voltage AlGaN-GaN power high-electron mobility transistors (HEMTs) on an insulating substrate were designed for the power electronics application. The field plate structure was employed for high breakdown voltage. The field plate length, the insulator thickness and AlGaN layer doping concentration were design parameters for the breakdown voltage. The optimization of the contact length and contact resistivity reduction were effective to reduce the specific on-resistance. The tradeoff characteristics between the on-resistance and the breakdown voltage can be improved by the optimization of the above design parameters, and the on-resistance can be estimated to be about 0.6 m/spl Omega//spl middot/cm/sup 2/ for the breakdown voltage of 600 V. This on-resistance is almost the same as that for the device on a conductive substrate.