Scanning probe microscopy specimen preparation

It should be noted that most of the microstructural data to be presented rely on different characterization techniques using electron microscopy in combination with other scanning probe microscopy techniques, e.g. scanning tunneling microscopy (STM) and atomic force microscopy (AFM). The details of specimen preparation and the analysis techniques of electron microscopy are described in other chapters of this book and are therefore not further covered in this chapter. The references provided in the chapter are merely a selection, since the field of research is vivid and the number of publications is large. The goal is to show the salient features which can be further explored by use of the referenced literature. 

The increased use of optical, electron, and scanning probe microscopies applied to polymer research has resulted from the widespread acceptance of these techniques combined with the need for higher performance and lower cost polymer materials. It is well known that the structures present in a polymer reflect the process variables and further that they greatly influence the physical and mechanical properties. Thus, the properties of polymer materials are influenced by their chemical composition, process history, and the resulting morphology. Morphological study involves two aspects prior to the study itself selection of instrumental techniques and development of specimen preparation methods. Structural observations must be correlated with the properties of the material in order to develop an understanding of the material. A major issue in the application of... 

The oldest microscopy technique for materials analysis was optical microscopy. Even to this day, for feature sizes above 1 pm, this is one of the most popular tools. For smaller features, electron microscopy techniques such as scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are the tools of choice. A third family of microscopy includes scanning probe tools such as scanning tunneling microscopy (STM) and atomic force microscopy (AFM). In these relatively recent techniques, sample preparation concerns are of minor importance compared to other problems, such as vibration isolation and processing of atomically sharp probes. Therefore, the latter techniques are not discussed here. This chapter is aimed at introducing the user to general specimen preparation steps involved in optical and electron microscopy [3 7], which to date are the most common... 

The shape and fimction of cytomembranes are intriguing and challenging research areas, inasmuch as their heterogeneous composition and size make them technically very difficult to study. Usually, we have to rely on experimental probes that inevitably perturb the sample - such as electron microscopy (EM) - to study their structures. The preparation techniques used for biological specimens often affect the shape of the membranes. Even if these obstacles can be overcome, the result is a two-dimensional impression of a three-dimensional structure. Serial sections or scanning electron microscopy (SEM), as well as tilting and rotation of the sample, will of course improve the result. 

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