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Optical-Based Thickness Measurement of MoO3 Nanosheets.

ABSTRACT: 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.

SUBMITTER: Puebla S

PROVIDER: S-EPMC7407517 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Optical-Based Thickness Measurement of MoO3 Nanosheets.

Puebla Sergio S Mariscal-Jiménez Antonio A Galán Rosalía Serna RS Munuera Carmen C Castellanos-Gomez Andres A

Nanomaterials (Basel, Switzerland) 20200629 7

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 ...[more]

PMID: 32610559

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