A GAAS/ALGAAS/INGAAS PSEUDOMORPHIC HEMT STRUCTURE FOR HIGH SPEED DIGITAL CIRCUITS
Abstract A double heterojunction GaAs/AlGaAs/InGaAs pseudomorphic depletion mode HEMT has been developed at the gate length of 80nm. The device properties are tested for different biasing potentials at the input and output side. The device is found to exhibit a cut off frequency of 80Ghz.Further, the logic suitability of the device is supported by developing the basic gates used for digital communication i.e. Inverter, Nand and Nor. Thus, enhancement in digital communication can be obtained with the use of HEMTs which provide high speed, low noise applications. Furthermore, with the implementation of universal gates using HEMTs, any digital circuit can be easily implemented. The paper reports a complete method from developing of the structure in Visual TCAD (VTCAD) to further implementing a circuit using the developed structure.