Center for Integrated Electronics, Department of Electrical, Computer and Systems Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
J Phys Condens Matter. 2010 Oct 6;22(39):395302. doi: 10.1088/0953-8984/22/39/395302. Epub 2010 Sep 10.
We fabricated a large number of single and bilayer graphene transistors and carried out a systematic experimental study of their low-frequency noise characteristics. Special attention was given to determining the dominant noise sources in these devices and the effect of aging on the current-voltage and noise characteristics. The analysis of the noise spectral density dependence on the area of graphene channel showed that the dominant contributions to the low-frequency electronic noise come from the graphene layer itself rather than from the contacts. Aging of graphene transistors due to exposure to ambient conditions for over a month resulted in substantially increased noise, attributed to the decreasing mobility of graphene and increasing contact resistance. The noise spectral density in both single and bilayer graphene transistors either increased with deviation from the charge neutrality point or depended weakly on the gate bias. This observation confirms that the low-frequency noise characteristics of graphene transistors are qualitatively different from those of conventional silicon metal-oxide-semiconductor field-effect transistors.
我们制备了大量的单双层石墨烯晶体管，并对其低频噪声特性进行了系统的实验研究。特别关注的是确定这些器件中的主要噪声源以及老化对电流-电压和噪声特性的影响。对噪声谱密度随石墨烯沟道面积的依赖关系的分析表明，低频电子噪声的主要贡献来自于石墨烯层本身，而不是来自于接触。由于暴露在环境条件下一个多月，石墨烯晶体管的老化导致噪声大大增加，这归因于石墨烯迁移率的降低和接触电阻的增加。无论是在单双层石墨烯晶体管中，噪声谱密度都随着偏离电荷中性点而增加，或者对栅极偏压的依赖性较弱。这一观察结果证实了石墨烯晶体管的低频噪声特性在质量上与传统的硅金属氧化物半导体场效应晶体管不同。
