IBM T. J. Watson Research Center , Yorktown Heights, New York 10598, United States.
ACS Nano. 2014 Jul 22;8(7):7333-9. doi: 10.1021/nn5024363. Epub 2014 Jul 7.
Carbon nanotubes (CNTs) continue to show strong promise as the channel material for an aggressively scaled, high-performance transistor technology. However, there has been concern regarding the contact resistance (Rc) in CNT field-effect transistors (CNTFETs) limiting the ultimate performance, especially at scaled contact lengths. In this work, the contact resistance in CNTFETs is defined in the context of a high-performance scaled transistor, including how the demonstrated Rc relates to technology targets. The impact of different source/drain contact metals (Pd, Pt, Au, Rh, Ni, and Ti) on the scaling of Rc versus contact length is presented. It is discovered that the most optimal contact metal at long contact lengths (Pd) is not necessarily the best for scaled devices, where a newly explored scaled metal contact, Rh, yields the best scaling trend. When extrapolated for a sub-10 nm transistor technology, these results show that the Rc in scaled CNTFETs is within a factor of 2 of the technology target with much potential for improvement through enhanced understanding and engineering of transport at the metal-CNT interface.
碳纳米管（CNTs）继续作为一种积极扩展的高性能晶体管技术的沟道材料显示出强大的前景。然而，人们一直担心碳纳米管场效应晶体管（CNTFETs）中的接触电阻（Rc）限制了其最终性能，尤其是在缩小的接触长度下。在这项工作中，CNTFETs 中的接触电阻是在高性能扩展晶体管的背景下定义的，包括所展示的 Rc 如何与技术目标相关。不同源/漏接触金属（Pd、Pt、Au、Rh、Ni 和 Ti）对 Rc 与接触长度的缩放关系的影响。研究发现，在长接触长度下（Pd）最优化的接触金属对于缩放器件来说不一定是最好的，新探索的缩放金属接触 Rh 产生了最佳的缩放趋势。当外推到亚 10nm 晶体管技术时，这些结果表明，缩放 CNTFETs 中的 Rc 与技术目标相差一个因子 2，通过增强对金属-CNT 界面处传输的理解和工程，可以大大提高其性能。
