Computational study on the performance comparison of monolayer and bilayer zigzag graphene nanoribbon FETs

Abstract

In our ab initio study on the device performance of nitrogen-doped monolayer zigzag GNR (ZGNR) FETs, an increase in ZGNR width from 0.92 nm to 1.78 nm degrades the I max/I min ratio due to the decrease in the energy bandgap (E g) which causes the I min to increase. It is also observed that the presence of vacancy at the edges of the channel ribbon can also open up an E g in ZGNRs as nitrogen dopants, and the performance of such device depends greatly on the vacancy concentration. In addition, simulation was carried out on the nitrogen-doped bilayer ZGNR FET and comparing to the monolayer ZGNR FET, the bilayer device provides a larger current while the I max/I min is lowered. ©2009 IEEE.