[21p-S011-1~20] 17.2 Graphene

△ [21p-S011-20] Carrier transport in highly-aligned bottom-up graphene nanoribbon array

〇(PC)Manabu Ohtomo¹, Yoshiaki Sekine¹, Hiroki Hibino^1,2, Hideki Yamamoto¹ (1.NTT Basic Research Labs., 2.Kwansei Gakuin Univ.)

Keywords:graphene nanoribbon,bottom-up,DBBA

We report carrier transport properties in highly-aligned bottom-up graphene nanoribbon (GNRs) arrays transferred from Au(788) template. We employed novel etching-free method, in which self-assembled monolayer of octanthiol was intercalated between GNR and Au(788). The transfer process without pottasium iodide etchant, which is widely-used gold etchant as well as strong dopant to organic molecules, enabled us to measure intrinsic transport property of GNRs. The nonlinear I-V characteristics was well-fitted by power-law dependence model, which was originally developed for 1-2 dimensional array of coulomb brocades. This result indicates that each GNR is working as quantum dot, with tunnel barrier between GNRs. After the sample was exposed to pottasium iodide etchant, though, the I-V characteristic turned into the double-exponential model, which is a typical characteristic for short channel schottkey diodes. This is due to the doping effect of iodine. The GNRs are heavily doped by iodine, which make the schottley barrier thin enough for tunneling. We will also report the gate voltage dependence of I-V characteristics and discuss the possible effect of Fermi-level pinning at electrode interface and short channel effect.