Monolayers and multilayers of polystyrene (PS)-gold composite films prepared by two different deposition methods have been investigated by atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and confocal Raman microspectroscopy. The intensity of the 1001 cm(-1) ring breathing mode of PS is used to evaluate the degree of ordering of monolayers and multilayers within a colloidal crystal. The depth profiling capability of confocal Raman microscopy is used to probe the regions inside the fractures in multilayered films. The intensity profile of the 1001 cm(-1) peak revealed the presence of fractures of different shapes with some PS microspheres at the bottom of the fracture. A strong increase in the Raman intensity (by 10(3) times) has been observed when probing the regions where Au nanoparticles are concentrated in aggregates of different shapes. This enhancement is attributed to the surface plasmons generated by the periodic structure of the gold nanoparticles.

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The simultaneous presence of hexagonal and quadratic arrangements of polystyrene microspheres in the top layers of polystyrene and gold-polystyrene composite colloidal crystals has been evidenced by both atomic force microscopy and scanning electron microscopy. It is thought that the formation of layers with the two different packing modes is in agreement with the phase transformations found in systems with confined geometries. The results of this study are relevant to the fabrication of high quality photonic crystals.