부산대학교 도서관

Electrostatic doping (ED)-based graphene nanoribbon (GNR) tunneling field-effect transistor (TFET) with trigate design is studied. The transfer and output characteristics of the GNR-TFET are explored using extended Hückel semiempirical method. An ${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}$ ratio as high as 10 14 is obtained with the ON-state current on the order of $10^{\textsf {3}}~\mu \text{A}/\mu \text{m}$ . A sub-60 mv/decade subthreshold swing is also observed (35 mv/decade). Armchair GNR with widths of 11 and 9 dimmers is found to be the best geometry to obtain a high ${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}$ ratio, and channel length of greater than 6.9 nm suppresses short-channel effect. The scaling behavior of the ED-based GNR-TFET is also studied. It is observed that a smaller gate-to-gate distance facilitate large ON-state current and small OFF-state current. Moreover, it is shown that for a high-quality switching performance, the lowest required built-in gate voltage must provide enough energy differential ${\Delta } \text{E}$ between the source- and drain-side energy bands.