Initial stage of crystalline rubrene thin film growth on mica (001)

• Published in: Synthetic metals 2011-02, Vol.161 (3-4), p.271-274
• Main Authors: Zaglmayr, H., Sun, L.D., Weidlinger, G., Al-Baqi, Sh.M. Abd, Sitter, H., Zeppenfeld, P.
• Format: Article
• Language: English
• Subjects: Coalescing; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Crystal structure; Crystallization; Epitaxial growth; Exact sciences and technology; Fibers; Fluorescence microscopy; Fluorescence spectroscopy; Islands; Mica; Nucleation; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of specific thin films; Organic thin films; Physics; Polymers; organic compounds; Rubrene; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Thin films
• ISSN: 0379-6779; 1879-3290
• DOI: 10.1016/j.synthmet.2010.11.033

We have studied the morphology and the spatially resolved photoluminescence of rubrene thin films at the early stage of crystallization. The initial growth proceeds via the formation of a wetting layer and the nucleation of islands with an amorphous structure. Crystallization starts when the amorphous islands coalesce and needle like crystalline fibers are formed in the gap between islands. The crystalline fibers then grow on top and in between the original amorphous islands leading to an “open network” of islands. The latter acts as the basis for the growth of semi-crystalline spherulites.