Electron Microscope: The Tool for Qualitative and Quantitative Analysis of Nano-Materials

Abstract

An electron microscope is a highly advanced sophisticated tool where high energy electron beam is used as the source. Since an electron beam has a shorter wavelength than visible light photons, it may expose the structure of tiny objects and has a higher resolving power than a light microscope. While most light microscopes are constrained by diffraction to around 500 nm resolution and usable magnifications below 2000, a scanning electron microscope (SEM) may attain 5 nm resolution and magnifications up to roughly 10,000,000. Electromagnetic lenses, which are similar to the glass lenses of an optical light microscope, are used in electron microscopes to create electron optical lens systems. Large molecules, biopsy samples, metals, crystals, and other biological and inorganic specimens, among others, can all have their ultrafine structure studied using electron microscopes. Electron microscopes are frequently used in industry for failure analysis and quality control. The images are captured using specialised digital cameras and frame grabbers by modern electron microscopes to create electron micrographs. To create an appropriate sample from materials for an electron microscope, processing may be necessary. Depending on the material and the desired analysis, a different procedure is needed. Transmission electron microscopes (TEM), scanning electron microscopes (SEM), reflection electron microscopes (REM), scanning tunnelling microscopes (STM), and other types of electron microscopes are commonly employed in academic and research institutions. The initial and operating costs of electron microscopes are higher and they are also more expensive to construct and maintain. High-resolution electron microscopes need to be kept in sturdy structures (often underground) with specialised amenities like magnetic field cancelling devices.<br>