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Register a new userOptical-based thickness measurement of MoO3 nanosheets
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Added by
Andres Castellanos-Gomez
Publication date
2020
fields
Physics
and research's language is
English
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Considering that two-dimensional (2D) molybdenum trioxide has acquired more attention in the last few years, it is relevant to speed up thickness identification of this material. We provide two fast and non-destructive methods to evaluate the thickness of MoO3 flakes on SiO2/Si substrates. First, by means of quantitative analysis of the apparent color of the flakes in optical microscopy images, one can make a first approximation of the thickness with an uncertainty of +-3 nm. The second method is based on the fit of optical contrast spectra, acquired with micro-reflectance measurements, to a Fresnel law-based model that provides an accurate measurement of the flake thickness with +-2 nm of uncertainty.
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