Dipartimento di Fisica E R Caianiello and Centro Interdipartimentale NANO_MATES, Università degli Studi di Salerno, via Ponte don Melillo, I-84084, Fisciano (Sa), Italy.
J Phys Condens Matter. 2013 Apr 17;25(15):155303. doi: 10.1088/0953-8984/25/15/155303. Epub 2013 Mar 25.
We produced graphene-based field-effect transistors by contacting mono- and bi-layer graphene by sputtering Ni or Ti as metal electrodes. We performed electrical characterization of the devices by measuring their transfer and output characteristics. We clearly observed the presence of a double-dip feature in the conductance curve for Ni-contacted transistors, and we explain it in terms of charge transfer and graphene doping under the metal contacts. We also studied the contact resistance between the graphene and the metal electrodes with larger values of ~30 kΩμm(2) recorded for Ti contacts. Importantly, we prove that the contact resistance is modulated by the back-gate voltage.
我们通过溅射 Ni 或 Ti 作为金属电极来接触单层和双层石墨烯，从而制备了基于石墨烯的场效应晶体管。我们通过测量器件的转移和输出特性来对其进行电特性表征。我们在 Ni 接触晶体管的电导曲线上清楚地观察到了双凹陷特征，并用金属接触下的电荷转移和石墨烯掺杂来解释这一特征。我们还研究了石墨烯与金属电极之间的接触电阻，对于 Ti 接触，记录到了约 30 kΩμm(2)的较大接触电阻。重要的是，我们证明了接触电阻可以通过背栅电压进行调制。
