부산대학교 도서관

AlGaN channel high electron mobility transistors (HEMTs) are the potential next step after GaN channel HEMTs, as the high aluminum content channel leads to an ultra-wide bandgap, higher breakdown field, and improved high temperature operation. Al 0.85 Ga 0.15 N/Al 0.7 Ga 0.3 N (85/70) HEMTs were operated up to 500 °C in ambient causing only 58% reduction of dc current relative to 25 °C measurement. The low gate leakage current contributed to high gate voltage operation up to +10 V under V ds = 10 V, with $\text{I}_{\mathrm{ ON}}/\text{I}_{\mathrm{ OFF}}$ ratios of $> 2 \times 10^{11}$ and 3 $\times \,\,10^{6}$ at 25 and 500 °C, respectively. Gate-lag measurements at 100 kHz and 10% duty cycle were ideal and only slight loss of pulsed current at high gate voltages was observed. Low interfacial defects give rise to high quality pulsed characteristics and a low subthreshold swing value of 80 mV/dec at room temperature. Herein is an analysis of AlGaN-channel HEMTs and their potential future for high power and high temperature applications.