Dynamic Performance Analysis of Logic Gates Based on p-GaN/AlGaN/GaN HEMTs at High Temperature

Abstract

The high-temperature operation of the AlGaN/GaN high electron mobility transistors (HEMTs) and direct-coupled FET logic (DCFL) inverters, NOR gates, and NAND gates are demonstrated. The <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">p</i> -GaN-gate HEMTs which are used as drivers in DCFL circuits exhibit proper E-mode operation with a relatively stable threshold voltage <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">TH</sub> (drift -0.31 V) and high electron mobility μ of 587 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /V∙S at 300 °C. The fabricated logic gates have a small switching time at room temperature (RT). As the temperature increases to 300 °C, these logic gates exhibit a slight increase in switching time, wherein the fall time and rise time of the inverter from room temperature to 300 °C increases from 16 ns to 129 ns and 128 ns to 0.864 μs, respectively. The logic gates herein exhibit accurate and stable operation at 300 °C. Furthermore, the reason for the switching time increase at high temperature is revealed from the perspective of devices.