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arXiv · 2205.01963

Reliable and Broad-range Layer Identification of Au-assisted Exfoliated Large Area MoS$_2$ and WS$_2$ Using Reflection Spectroscopic Fingerprints

Bo Zou·Yu Zhou·Yan Zhou·Yanyan Wu·Yang He·Xiaonan Wang·Jinfeng Yang·Lianghui Zhang·Yuxiang Chen·Shi Zhou·Huaixin Guo·Huarui Sun
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Abstract

The emerging Au-assisted exfoliation technique provides a wealth of large-area and high-quality ultrathin two-dimensional (2D) materials compared with traditional tape-based exfoliation. Fast, damage-free, and reliable determination of the layer number of such 2D films is essential to study layer-dependent physics and promote device applications. Here, an optical method has been developed for simple, high throughput, and accurate determination of the layer number for Au-assisted exfoliated MoS$_2$ and WS$_2$ films in a broad thickness range. The method is based on quantitative analysis of layer-dependent white light reflection spectra, revealing that the reflection peak intensity can be used as a clear indicator for determining the layer number. The simple yet robust method will facilitate the fundamental study on layer-dependent optical, electrical, and thermal properties and device applications of 2D materials. The technique can also be readily combined with photoluminescence and Raman spectroscopies to study other layer-dependent physical properties of 2D materials.

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Bo Zou, Yu Zhou, Yan Zhou, Yanyan Wu, Yang He, Xiaonan Wang, Jinfeng Yang, Lianghui Zhang, Yuxiang Chen, Shi Zhou, Huaixin Guo, Huarui Sun. 2022-05-04. Reliable and Broad-range Layer Identification of Au-assisted Exfoliated Large Area MoS$_2$ and WS$_2$ Using Reflection Spectroscopic Fingerprints. https://doi.org/10.1007/s12274-022-4418-z

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