Noise Analysis of Monolayer Graphene Nanopores

Noise Analysis of Monolayer Graphene Nanopores

Zi-Yin Zhang, Yun-Sheng Deng, Hai-Bing Tian, Han Yan, Hong-Liang Cui, and De-Qiang Wang

Int. J. Mol. Sci. 2018, 19(9), 2639; https://doi.org/10.3390/ijms19092639

Graphene-based nanopore devices show significant promise in single molecule detection due to their monoatomic membrane thickness, closely matching the spacing between nucleobases. However, high noise levels, particularly at low frequencies, hinder their practical application. This study examines the impact of suspended graphene area on noise levels across the full frequency spectrum. Monolayer graphene films were transferred onto SiNx substrates with pre-patterned holes of various diameters to create self-supported films, which were then perforated with nanoscale holes. Experimental results indicate that low-frequency 1/f noise depends on the geometry of the underlying SiNx. The suspended graphene area influences capacitance and high-frequency noise, affecting noise levels over a wide frequency range. Additionally, low-frequency noise shows minimal dependency on salt concentration, deviating from Hooge’s relation. These insights provide a comprehensive understanding of noise characteristics and offer guidance for designing free-standing monolayer graphene nanopore devices.

Keywords: monolayer graphene; solid-state nanopore; suspended area; noise; power spectral density