Development of the method – Silicon thin film profilometry using Raman spectroscopy

Authors

Martin Ledinský, Bertrand Paviet-Salomon, Aliaksei Vetushka, Jonas Geissbühler, Andrea Tomasi, Matthieu Despeisse, Stefaan De Wolf , Christophe Ballif & Antonín Fejfar

Laboratory / Department
Thin Films
Citation
https://doi.org/10.1038/srep37859
DOI
10.1038/srep37859
Year
2016

Within the European project Horizon 2020 - NextBase, we developed several characterization methods suitable for extremely thin layers (with a thickness below 20 nm). One of these methods utilizes the absorption of the Raman scattering signal of crystalline silicon by a thin layer of amorphous silicon deposited on this substrate. This non-contact method allows us to precisely determine the thin film thicknesses with a significant surface roughness. The method has been identified as a fundamental result of the EU project, therefore, we continue its development.

a) Raman spectra measured on the a-Si:H stripe (blue line) and on an uncovered part of the flat c-Si wafer (orange line); b) Sketch of the test sample; c) Corresponding Raman map of c-Si integral intensities integrated over 505-535 cm-1 range.
a) Raman spectra measured on the a-Si:H stripe (blue line) and on an uncovered part of the flat c-Si wafer (orange line); b) Sketch of the test sample; c) Corresponding Raman map of c-Si integral intensities integrated over 505-535 cm-1 range.

Cooperating institutions:

  • PV-Center, Centre Suisse d’Électronique et de Microtechnique, Rue Jaquet-Droz 1, CH-2002 Neuchâtel, Switzerland (Bertrand Paviet-Salomon, Jonas Geissbühler, Matthieu Despeisse & Christophe Ballif)
  • École Polytechnique Fédérale de Lausanne (EPFL), Institute of microengineering (IMT), Photovoltaics and Thin Film Electronics Laboratory, Rue de la Maladière 71b, CH-2000 Neuchâtel, Switzerland (Andrea Tomasi & Christophe Ballif)
  • King Abdullah University of Science and Technology (KAUST), KAUST Solar Center (KSC), Thuwal, 23955-6900, Saudi Arabia (Stefaan De Wolf)