Investigation of emerging graphene field effect transistors for low power applications

Abstract

The onset of VLSI industry started with big sized chips with some thousand number of transistors incorporating several functionalities. Transistor dimension used then was some hundreds of micometer. This has stepped towards more lowering in transistor dimensions with shrinking chip size, increased chip efficiency as well as reduction in cost per transistor. Transistor dimensions below ten of nanometers for eg- 7nm, 5nm shows significant degradation in performance and efficiency of and integrated chip because of many effects such as leakage current, short channel effects, drain induces barrier lowering and many more at such low level. Many technologies were developed to sustain the ill effects. silicon-on-insulator, incorporated silicon-insulator-silicon-substrate instead of conventional silicon substrate. It served reduced parasatics and an increased performance. Upcoming upcoming advance devices such as FinFets, single electron transistor (SET) have also gained increased research attention due to their superior performance than the conventional silicon based devices. The new emerging materials born from carbon, graphene and carbon nanotubes are the most potential and suitable candidates for future electronics. These materials offer magnificient properties which can be used to model digital circuits and systems for high end applications. Essential analytical modeling is being done to extract the I-V characteristics of graphene based transistors. This is important so as to have some insight of the device design parameters on the I-V characterstics. Digital circuits based on graphene and carbon nano tube field effect transistors were being simulated and compared against their silicon counterparts. The results show that graphene FETs perform much better out of the three. Memory designing and low noise amplifier for biomedical application have been being carried out with both the materials as well as silicon. The results shows that digital circuits as well as analog designs simulated with graphene FETs and CNTFETs are 50% more better than silicon FETs in terms of performance and efficiency.