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arXiv · 1702.07534

Non-invasive Scanning Raman Spectroscopy and Tomography for Graphene Membrane Characterization

Stefan Wagner·Thomas Dieing·Alba Centeno·Amaia Zurutuza·Anderson D. Smith·Mikael Östling·Satender Kataria·Max C. Lemme
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Abstract

Graphene has extraordinary mechanical and electronic properties, making it a promising material for membrane based nanoelectromechanical systems (NEMS). Here, chemical-vapor-deposited graphene is transferred onto target substrates to suspend it over cavities and trenches for pressure-sensor applications. The development of such devices requires suitable metrology methods, i.e., large-scale characterization techniques, to confirm and analyze successful graphene transfer with intact suspended graphene membranes. We propose fast and noninvasive Raman spectroscopy mapping to distinguish between freestanding and substrate-supported graphene, utilizing the different strain and doping levels. The technique is expanded to combine two-dimensional area scans with cross-sectional Raman spectroscopy, resulting in three-dimensional Raman tomography of membrane-based graphene NEMS. The potential of Raman tomography for in-line monitoring is further demonstrated with a methodology for automated data analysis to spatially resolve the material composition in micrometer-scale integrated devices, including free-standing and substrate-supported graphene. Raman tomography may be applied to devices composed of other two-dimensional materials as well as silicon micro- and nanoelectromechanical systems.

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Stefan Wagner, Thomas Dieing, Alba Centeno, Amaia Zurutuza, Anderson D. Smith, Mikael Östling, Satender Kataria, Max C. Lemme. 2017-02-24. Non-invasive Scanning Raman Spectroscopy and Tomography for Graphene Membrane Characterization. https://doi.org/10.1021/acs.nanolett.6b04546

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