A theoretical model for metal-graphene contact resistance using a DFT-NEGF method
A theoretical model for metal-graphene contact resistance using a DFT-NEGF method
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DOI：
10.1039/c3cp52589a
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发表时间：
2013-01-01
影响因子：
3.3
通讯作者：
Yu, Zhiping
中科院分区：
文献类型：
--
作者：
Ji, Xiang;Zhang, Jinyu;Yu, Zhiping
石墨烯和金属电极之间的接触电阻（Rc）对于实现石墨烯器件的潜在高性能至关重要。然而，先前基于Landauer方法的分析模型未能包括金属下的石墨烯与纯石墨烯通道之间的费米速度差。在此，我们报告了一个理论模型，估计Rc使用密度泛函理论和非平衡绿色函数的方法。我们的模型不仅提出了一个清晰的物理图像的金属-石墨烯接触，但也产生R-C值，这是在很好的协议与实验结果：210 Ω μ m的双面Pd接触相比，403 Ω μ m的单面Pd接触。
The contact resistance (R-c) between graphene and metal electrodes is of crucial importance for achieving potentially high performances for graphene devices. However, previous analytical models based on Landauer's approach have failed to include the Fermi velocity difference between the graphene under the metal and the pure graphene channel. Hereby we report a theoretical model to estimate the Rc using density-functional theory and non-equilibrium Green's function methods. Our model not only presents a clear physical picture of the metal-graphene contacts, but also generates R-c values which are in good agreement with the experimental results: 210 Omega mu m for double-sided Pd contacts compared with 403 Omega mu m for single-sided Pd contact.