Microscopic investigation of the poly(9,9-dioctylfluorene) photoluminescence dependence on the deposition conditionsby confocal laser microscopy

• Published in: Applied physics letters 2006-05, Vol.88 (18), p.181906-181906-3
• Main Authors: Caruso, M. E., Lattante, S., Cingolani, R., Anni, M.
• Format: Article
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.2200008

We studied the microscopic dependence of poly(9,9-dioctylfluorene) photoluminescence (PL) on the deposition conditions. We show that in films spin coated from chloroform phase separation of β and glassy phases is present, with micrometric β phase clusters covering about 6% of the sample surface. The exposure to toluene vapors leads to the disappearance of the β phase clusters, but increases the β phase content in the films due to swelling induced polyfluorene chain planarization. The deposition from toluene solution leads to nonuniform PL intensity, dominated by the β phase emission, attributed to an interplay between aggregation during the solvent evaporation and solvent swelling induced chain planarization.