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The impact of the chemical environment on heterogeneous electron transfer processes of two perylene derivatives chemically bound to ZnO or TiO2colloids in a film was investigated by means of absorption and fluorescence spectroscopy. The perylene molecules varied in their electronic coupling between the perylene moiety and a carboxylic acid group, which also bound the perylene dyes to the semiconductor surface. Significantly different excited state dipole moments for the two perylene derivatives were found for certain perylene−solvent interactions and were attributed to different intramolecular charge transfer characters of the excited state. It is concluded that lifetime broadening due to ultrafast electron injection plays only a minor role in explaining the observed strong broadening of the absorption spectra for the hybrid systems with strong electronic coupling. Rather, a strong environmental effect of the colloidal semiconductor has to be taken into account for the hybrid systems with strong interfacial couplings.

Latent images obtained by deep-ultraviolet (DUV) patterning and post-exposure bake in the polymer system poly(t-butylmethacrylate) (PTBMA) resist/triphenyl sulfonium photoacid generator are characterized by infrared near-field microscopy (IR-NSOM). Chemical sub-group specificity is achieved in the infrared near-field images by using wavelengths tuned on the OH absorption band of the poly(methacrylate acid) (PMAA) resulting from the photoacid-catalyzed decomposition of t-butoxycarbonyl groups. The experimental images of the patterned thin polymer film are compared with predictions based on scalar diffraction theory calculations for the initial light illumination step through the mask. Partial disagreement between the theory and the experiment is observed, but only for certain line/space dimensions of the pattern. The results suggest a structure-dependent chemistry during the latent image development.

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