Characterization of polymer thin films by phase-sensitive acoustic microscopy and atomic force microscopy: a comparative review

The potential of phase-sensitive acoustic microscopy (PSAM) for characterizing polymer thin films is reviewed in comparison to atomic force microscopy (AFM). This comparison is based on results from three-dimensional vector contrast imaging and multimodal imaging using PSAM and AFM, respectively. The similarities and differences between the information that can be derived from the AFM topography and phase images, and the PSAM phase and amplitude micrographs are examined. In particular, the significance of the PSAM phase information for qualitative and quantitative characterization of the polymer films is examined for systems that generate surface waves, and those that do not. The relative merits, limitations and outlook of both techniques, individually, and as a complementary pair, are discussed.