Optimum Carbon Concentration in GaN-on-Silicon for Breakdown Enhancement in AlGaN/GaN HEMTs

This article reports on the experimental and analytical determination of the optimum carbon concentration in GaN to achieve enhanced breakdown in AlGaN/GaN high-electron mobility transistors (HEMTs). The lateral breakdown voltage increases when carbon doping is increased from $3\times 10^{{18}}$ to 1019 cm−3 beyond which it decreases, whereas there is no substantial enhancement in the vertical b...