A-Z-A型石墨烯场效应晶体管吸附效应的第一性原理研究

First-principles study of adsorption effect of A-Z-A graphene nanoribbons field effect transistor

利用第一性原理的计算方法,研究了A-Z-A型GNR-FET的电子结构和输运性质及其分子吸附效应.得到了以下结论:纯净的A-Z-A型GNR-FET具有典型的双极型晶体管特性,吸附分子的存在会使纳米带能隙变小.对于吸附H,H_2,H_2O,N_2,NO,NO_2,O_2,CO_2和SO_2分子的情况,A-Z-A型GNR-FET仍然保持着场效应晶体管的基本特征,但吸附不同类型的分子会使GNR-FET的输运特性发生不同程度的改变;对于吸附OH分子的情况,输运特性发生了本质的改变,完全不具有场效应晶体管的特性.这些研究结果将有助于石墨烯气体探测器的工程实现,并对应用于不同环境巾GNR-FET的设计具有重要指导意义.

By performing first-principles calculations,we demonstrate the electronic structure,the transport properties,and the adsorption effect of A-Z-A graphene nanoribons field effect transistor.It is concluded that the pure A-Z-A GNR-FET has typical bipolar characteristics, and energy gaps will become smaller due to the adsorbed molecule.For the adsorption of H,N_2,NO_2,H2O,SO_2,O_2 and NO,A-Z-A GNR-FET remains typical bipolar characteristic,but shows a little difference in transport property after it has adsorbed different types of molecles.For the adsorption of OH,transport property changes totally and does not have a bipolar characteristic any more.These results may contribute to the implementation of gas detector based on GNRs and the design of GNR-FET applied in complex environments.