2D-Materials

What is unique about an imaging ellipsometer?

Imaging ellipsometers offer a unique capability to perform spectroscopic ellipsometric measurements on two-dimensional (2D) material flakes
as small as 1 µm. They generate high-resolution microscopic maps of thickness distributions and refractive indices across a wide spectral range from 190 to
1700 nm. With Ellipsometric Contrast Micrographs (ECM), users can achieve
significantly enhanced contrast compared to conventional optical microscopy, making it easier to visualize layer numbers and detect inhomogeneities. These systems also support non-destructive measurements on transparent
substrates by employing knife-edge illumination, which effectively eliminates unwanted backside reflections.

Key Features

Imaging spectroscopic ellipsometry can be applied to characterize graphene and other 2D-materials. CVD grown, exfoliated and epitaxially grown flakes of 2D-materials are analyzed with the imaging ellipsometer ep4.

Imaging of monolayers on different substrates
Determination of the optical dispersion
Distinction between mono-, bi- or n-layers
Automatic flakesearch algorithm for identification of monolayers or well-defined thickness regions
Exploration of heterostructures
Quality control by detecting defects and special aspects of 2D nanoplates

Brochure

Compendium: Graphene and 2D-Materials

Beyond Graphene_Microscopic Characterization of 2D Materials by SIE

Characterisation of 2D Materials by SIE and RSE

Full scale wafer analysis by imaging ellipsometry and ellipsometric contrast micrography

Spectroscopic Ellipsometry and Optical Constants of MoS2 Flakes

Imaging Mueller Matrix Ellipsometry for Anisotropic Samples of Black Phosphorus

Characterization of Graphene through Imaging Spectroscopic Ellipsometry

MoS₂-WSe₂ Investigated by Imaging Ellipsometry

Automatic Localization of Mono- to N-Layers 2D Materials by Spectroscopic Imaging Ellipsometry

Literature

Voltage-Controlled Dielectric Function of Bilayer Graphene (2020)

Giant Optical Anisotropy in Transition Metal Dichalcogenides for Next-Generation Photonics (2020)

Fast, Noncontact, Wafer-Scale, Atomic Layer Resolved Imaging of Two-Dimensional Materials by Ellipsometric Contrast Micrography (2018)

Manifold Coupling Mechanisms of Transition Metal Dichalcogenides to Plasmic Gold Nanoparticle Arrays (2018)

Imaging Spectroscopic Ellipsometry of MoS2 (2016)

Spectroscopic Imaging Ellipsometry for Automated Search of Flakes of Mono- and N-Layers of 2D Materials (2016)

Spectroscopic Imaging Ellipsometry and Fano Resonance Modeling of Graphene (2012)

High Resolution Imaging of Few-Layer Graphene (2012)

Imaging Ellipsometry of Graphene (2010)

Characterization of Thermally Reduced Graphene Oxide by Imaging Ellipsometry (2008)