On Time Delay Analysis Of Gan HEMT Inverter

The properties of Gallium Nitride (GaN) devices like high breakdown voltage, high operating voltage, high thermal stability and high electron mobility aids in the integration of power amplifiers, drive circuits and logic circuits based on GaN High Electron Mobility Transistors (HEMTs). In this paper, a detailed time delay analysis of the GaN HEMT based inverter is performed. The physical parameters like the Back Barrier (BB) material Extensive research is going on the application of GaN based HEMTs in high-speed digital systems. and the gate structure are varied to investigate the time delay of the inverter. The time delay analysis was performed on the inverter designed using Aluminum GaN (AlGaN)/GaN HEMT on GaN substrate at 800 nm gate length. The BB materials like AlGaN, BGaN, AlN and AlInN were incorporated. Among the devices with BB, the device with the AlInN BB exhibited the best performance with a propagation delay of 11.5 ps and a rise time and fall time of 11.6 ps and 11.4 ps respectively. Further, the performance investigation of GaN HEMT without the BB revealed better results with a propagation delay of 10.6 and a rise time and fall time of 7.7 ps. The analysis was also done with T-gate GaN HEMT with and without BB. The T-gate GaN HEMT with AlGaN BB exhibited a propagation delay of 9 ps and rise and fall time of 7.5 and 7.6 ps respectively. The T-gate GaN HEMT without BB exhibited similar performance with a propagation delay of 9.5 ps and a rise time and fall time of 6.9 ps. The HEMT with T-gate exhibited lower rise and fall times along with less propagation delay. The T gate GaN HEMT based logic gates are the best candidate for the application in high-speed digital circuits in Embedded Vision System (EVS).