Nanoscale optical microscopy of conjugated polymer films

Near-field scanning optical microscopy (NSOM) has been used to probe the ph otoluminescence, linear dichroism and photoconductivity of free-standing po ly(p-phenylene vinylene) (PPV) films with spatial resolution better than 10 0 nm. We observe a strong correlation between each of these properties and film morphology in both non-oriented and stretch-oriented films. The nan-or iented PPV thin films exhibit mesoscale non-uniform photoluminescence corre lated to polymer clusters. Upon stretch-orientation, PPV thin films show av erage polymer chain orientation parallel to the stretch axis as well as dis tinct areas of perpendicular molecular orientation correlated to film topog raphy.