Technology Offer Highly conductive, transparent carbon films MI 0903-3685 ZLC Max-Planck-Innovation GmbH Amalienstr. 33 80799 Munich Germany Background Phone: +49 (89) 29 09 19 - 0 Fax: +49 (89) 29 09 19 - 99 [email protected] www.max-planck-innovation.de Fabrication of new transparent conductive films to serve as electrodes has long been pursued for modern optoelectric devices since availability of element Indium contained in traditional ITO is questionable. Contact Dr. Lars Cuypers Phone: +49 (89) 29 09 19 - 21 [email protected] Technology An optical transparent conductive carbon film, comprising a supramolecular assembly of discotic molecules and the use of this film in several technical devices like displays, diodes and solar cells is patented. Discotic molecules like C96-C12 or HBC-PhC12 - but also graphene oxide or cheap polycyclic aromatics containing raw materials like tar pitch - are spin-coated from a solution onto quartz and heated from 400 – 1100 °C under argon protection. Fig. 1: Illustration of the intermolecular condensation of nanographene into graphene film. The temperature program starts at low temperatures, to avoid evaporation of the discotic molecules. The discotic molecules connect by and by and the temperature can be increased slowly. Finally this leads to a smooth, complete graphene surface. The thickness of the resulting carbon films can be controlled easily by the concentration of the starting solutions. Carbon films grown on 300 nm SiO2 with a thickness between 3.5 nm and 30 nm show a sheet resistance (Rs) in the range 20 – 500 ohm/sq respectively 1 – 15 ohm/sq. The thin carbon films show advantages not only over traditional ITO in their thermal and chemical stability but over carbon nanotube films in their extremely smooth surface. Literature X. Wang, L. Zhi, N. Tsao, Z. Tomovic, J. Li, K. Muellen: " Transparent Carbon Films as Electrodes in Organic Solar Cells", Angew. Chem. Int. Ed. 2008, 47, 2990 –2992 X. Wang, L. Zhi, K. Muellen: " Transparent, Conductive Graphene Electrodes for Dye-Sensitized Solar Cells", Nano Lett., Vol. 8, No. 1, 2008 A. Vollmer, X.L. Feng, X.Wang, L.J. Zhi, K. Muellen, N. Koch, J.P. Rabe: "Electronic and structural properties of graphene-based transparent and conductive thin film electrodes", Appl Phys A (2009) 94: 1–4 Patent Information PCT priority patent application filed in 2007. nationalized in EP, US, CA, BR, JP, CN, KR, RU, ZA ZA200907233 CN0880018550 RU2472824 JP5564417 KR101431171 granted in 2010 granted in 2013 granted in 2013 granted in 2014 granted in 2014