The impact of the intrinsic time-dependent fluctuations in the electrical resistance at the graphene–metal interface or the contact noise, on the performance of graphene field-effect transistors, can be as adverse as the contact resistance itself, but remains largely unexplored. Here we have investigated the contact noise in graphene field-effect transistors of varying device geometry and contact configuration, with carrier mobility ranging from 5,000 to 80,000 cm2 V−1 s−1. Our phenomenological model for contact noise because of current crowding in purely two-dimensional conductors confirms that the contacts dominate the measured resistance noise in all graphene field-effect transistors in the two-probe or invasive four-probe configurations, and surprisingly, also in nearly noninvasive four-probe (Hall bar) configuration in the high-mobility devices. The microscopic origin of contact noise is directly linked to the fluctuating electrostatic environment of the metal–channel interface, which could be generic to two-dimensional material-based electronic devices.
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机译：石墨烯-金属界面处的电阻固有的时间依赖性波动或接触噪声对石墨烯场效应晶体管的性能的影响可能与接触电阻本身一样不利，但很大程度上尚待探索。在这里，我们研究了不同器件几何形状和接触配置的石墨烯场效应晶体管的接触噪声，载流子迁移率范围为5,000至80,000 cm 2 V -1 s < sup> -1 。由于电流在纯二维导体中拥挤而导致的接触噪声的现象学模型，证实了接触在两个探针或侵入性四探针配置中的所有石墨烯场效应晶体管中的测得的电阻噪声中占主导地位，而且令人惊讶的是，在几乎高机动性设备中的无创四探针（霍尔杆）配置。接触噪声的微观起源直接与金属-通道界面的波动静电环境有关，这可能是二维基于材料的电子设备所通用的。
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