Morphology, fluorescence properties, and their photothermal changes of poly(substituted thiophene) films revealed by near-field fluorescence microspectroscopy.

The morphology and fluorescence spectrum of poly{3-[2-(N-dodecylcarbamoyloxy)ethyl]thiophene-2,5-diyl} film were examined with spatial resolution of 100 nm using near-field fluorescence microspectroscopy. Fluorescence spectra observed at protruding domains were blue-shifted compared with flat areas, and further blue-shift was observed there more appreciably by long-time irradiation via a near-field scanning optical microscope probe. It is considered that the polymer chains at the protruding domains take disordered conformations, in which conjugated lengths are shorter and further disordering can be induced more easily by irradiation compared with those in the flat areas.