The Effective Mass, Band Gap, Device Characteristics, and Performance Considerations for AGNR and AGNRFETs

In this paper, we introduce our work on material characteristics, device characteristics, and performance considerations for armchair graphene nanoribbons (AGNRs) and AGNR field-effect transistors (AGNRFETs). First, we show that the effective-mass-versus-band-gap relationship can be described by a group of lines. By simply tight-binding a model considering only the first-nearest neighbor interaction, the effective-mass-versus-band-gap relationship for AGNRs can be described by two lines crossing zero, which is further separated into three lines if considering third-nearest neighbor interaction and edge bond relaxation. Second, we show the quantum transport calculations for AGNRFETs. We found that a smaller/larger off-state leakage current in the $I_{D}$ – $V_{G}$ curve may be always accompanied with a smaller/larger on-current in the $I_{D}$ – $V_{D}$ curve, which is then explained by full complex band structure characteristics. Finally, we show that, to achieve a certain on-current–off-current ratio for 10-nm AGNRFETs, smooth edges are needed for AGNRs with a width of about 3 nm at most.