Raster-scanned scanning force microscopy

A number of methods are available for the characterization and examination of SAMs as well as for the observation of the reactions with the immobilized biomolecules. Only some of these methods are mentioned briefly here. These include surface plasmon resonance (SPR) [46], quartz crystal microbalance (QCM) [47,48], ellipsometry [12,49], contact angle measurement [50], infrared spectroscopy (FT-IR) [51,52], Raman spectroscopy [53], scanning tunneling microscopy (STM) [54], atomic force microscopy (AFM) [55,56], sum frequency spectroscopy. X-ray photoelectron spectroscopy (XPS) [57, 58], surface acoustic wave and acoustic plate mode devices, confocal imaging and optical microscopy, low-angle X-ray reflectometry, electrochemical methods [59] and Raster electron microscopy [60]. 

The relatively novel method of atomic force microscopy can be used both ex situ and in situ for the study of the surface morphology of electrodes. It is based on a thin and sensitive cantilever to which a sharp microscopic tip is attached. The tip is raster-scanned along the studied surface, changing its deflection as a result of topographic changes. The deflection is measured by a laser beam which is reflected from the back of the cantilever to a detector that measures the position... 

The PUs microstructure can be also investigated by means of atomic force microscopy (AFM). Phase images obtained via AFM, enable visual representation of the PUs microphase separated morphology. AFM records the surface topography of materials by measuring attractive or repulsive forces between the probe and the sample. Vertical deflections caused by surface variations are monitored as a raster scan drugs a fine tip over the sample. A detailed description of different modes in AFM technology has been described in [195]. 

Atomic force microscopy (AFM) is emerging as a popular technique for the characterization of nanomaterials. A sharp probe or tip affixed to the end of a cantilever is raster scanned over the surface of the sample to be imaged, in this... 

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