Pentacene thin-films obtained by thermal evaporation in high vacuum

Pentacene thin-films were obtained by thermal evaporation in high vacuum of a pure (98%) commercially available source. All the samples were grown at room temperature (25 °C) and high deposition rates (>20 Å/s) on Corning glass substrates. The microstructure of the pentacene thin-films evidences the coexistence of thin-film and bulk triclinic crystalline phases. The optical absorption edge close to 1.7 eV, together with the high optical absorption in the visible range, make pentacene a promising candidate for low cost solar cells. Doping series of samples were obtained by dipping pieces cut from the same pentacene sample into a solution of iodine in acetonitrile for different times (