Deconvolution of atomic force microscopy data for cellular and molecular imaging

The restoration of image features in cellular and molecular images is a crucial problem in nanobiological investigations. Scanning probe microscopy (SPM) offers the potential for direct investigative capability at nanometer resolution necessary for imaging biological units and macromolecular protein control blocks. The distortion of the measured image due to tip-sample interaction is a major challenge for nanoscale metrology, and signal processing solutions are needed for increasing the accuracy and reliability of the data. Two candidate approaches have been described in detail in this article for modeling the tip-sample interaction from a topographical perspective, which is then used for reconstructing the sample surface from known tip geometry. When the aspect ratio of a feature is comparable with that of the tip, the two methods produce similar results, but when the aspect ratio is larger than that of the tip, the MM method produces a sharper estimate than the LT method. When the tip geometry is not known, blind-tip estimations methods are needed for iterative estimations of tip and sample surfaces.