Semi-Empirical DFT Based Investigation of Electronic and Quantum Transport Properties of Novel GS-AGNR (N) FET

Abstract

In this article, the electronic and quantum transport properties for the bulk configuration of armchair graphene nanoribbons (AGNRs) with varied number of carbon atoms along AGNR width (N) are investigated. The semi-empirical (SE) Density Functional Theory (DFT) approach is used to calculate the band structure, density of states (DOS), and transmission spectrum for the bulk configuration of AGNR. Further, the AGNRs are used in channel material to analyze the performance of field-effect transistors with Gate Stack (GS) architecture. The result shows that the bandgap value is higher for AGNR (N = 4) with a value of 1.98 eV compared to another bulk configuration of AGNRs. In addition to this, AGNR (N = 4) also shows an improved transmission spectrum. Moreover, the transmission spectrum at varied input voltages and projected local density of states (PLDOS) are also analyzed to study the performance of the proposed devices. The parameters mentioned above give a unique idea for evaluating the performance in terms of resonance peaks and electronic structure for device configurations. The off current (I _off ) is remarkably reduced, and the switching ratio (I _on /I _off ) is significantly improved in GS-AGNR (N = 4) FET compared with other device configurations. Owing to the enhanced switching, this paper highlights GS-AGNR (N = 4) FET as a suitable candidate for low-power applications such as low-power sensors, wireless communication, and medical devices.