Basic Microscopic Techniques to Characterize Nano Materials

It is not surprising that materials with nanoscale dimensions have existed since the creation of the universe. The reason is simple since all the materials are composed of different atoms or molecules, so an assembly of a few molecules can give rise to what one calls “nanomaterials”. The concept of nano, or more specifically, nanoscience and technology, is relatively new, as it requires a long journey of technological advancement to develop distinct optical devices that can see materials with dimensions of 10-9 metres and thus manipulate them for greater purposes. These special devices are commonly known as microscopes; however, they are not the same as traditional microscopes, which have a maximum resolution of 10-6 (micro) meters. In this chapter, the basic constructions and working principles of the more commonly used microscopes, rather than nanoscopes, will be discussed. Discussions on field emission scanning electron microscope (FESEM), high-resolution transmission electron microscopes (HRTEM), and scanning tunnelling microscope (STM) will also be done. Besides, the name and the main working principle of some other microscopic techniques will be mentioned. Apart from imaging, some other uses (if any) of these devices would also be mentioned.

Keywords: AFM, FESEM, Microscopy, Resolving power, Resolution, SPM, STM, TEM.