Industry 4.0
Vol. 10 (2025), Issue 5, pg(s) 174-177

DOMINANT TECHNOLOGIES IN “INDUSTRY 4.0”

Surface Characterization of 2D Layers for Sensor Applications using SEM and 3D Laser Microscopy

  • 1 Department of Sensor Information Systems and Technologies, Institute of Informatics, Slovak Academy of Sciences, Bratislava, Slovak Republic
  • 2 Institute of Electronics, Bulgarian Academy of Sciences, Bulgaria

Abstract

Two-dimensional (2D) materials such as graphene and tungsten disulfide (WS₂ ) are promising candidates for gas sensors due to their unique electrical and surface properties. Graphene exhibits high conductivity and mechanical strength, while its oxidized or functionalized forms enhance chemical reactivity and gas adsorption. WS₂ , a semiconducting transition metal dichalcogenide, shows strong surface interactions with gases, enabling sensitive detection even at room temperature.
In this work, graphene and WS₂ thin films were characterized to evaluate surface morphology, uniformity, and structural quality. Graphene films were prepared by chemical vapor deposition (CVD) and transferred onto SiO₂ /Si substrates, while WS₂ films with thicknesses of 20 nm and 50 nm were obtained via CVD and sputtering. Surface analysis using scanning electron microscopy (SEM) and 3D laser microscopy revealed that graphene films are highly uniform and smooth, whereas WS₂ films exhibit thickness-dependent surface roughness and texture. These findings provide insights into the relationship between film morphology and gas sensing performance, highlighting the potential of both materials for sensor applications.

Keywords

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