Noninvasive Scanning Raman Spectroscopy and Tomography for Graphene Membrane Characterization
2017 (English)In: Nano letters (Print), ISSN 1530-6984, E-ISSN 1530-6992, Vol. 17, no 3, 1504-1511 p.Article in journal (Refereed) Published
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.
Place, publisher, year, edition, pages
American Chemical Society (ACS), 2017. Vol. 17, no 3, 1504-1511 p.
Raman spectroscopy, Raman tomography, suspended graphene, noninvasive, strain, doping, nanoelectromechanical systems, NEMS, MEMS, 2D materials
Computer and Information Science
IdentifiersURN: urn:nbn:se:kth:diva-204070DOI: 10.1021/acs.nanolett.6b04546ISI: 000396185800027PubMedID: 28140595ScopusID: 2-s2.0-85014955224OAI: oai:DiVA.org:kth-204070DiVA: diva2:1085514
QC 201703292017-03-292017-03-292017-03-29Bibliographically approved