Scanning Electron Microscope (SEM)
In Scanning Electron Microscopy (SEM), the electron beam is focused on the entire material being examined. The surface is scanned in a specific pattern. The accelerating voltage ranges from 100 V to 30 kV. SEM allows for magnifications of up to 100,000 times. Due to its large format, it creates a strong three-dimensional effect.
The scan appears in a single color (monochromatic). This is because only a specific energy is used, and the values are automatically converted to a particular color in the image. If desired, the image can be colored later through image editing. In the industry, SEM is often used for detecting asbestos fibers and ceramic fibers.
Another term often used for Scanning Electron Microscopy is Raster Scanning, because the microscope scans a certain grid (Raster). However the term frequently used is Scanning Electron Microscopy.
Another method, besides SEM, for determining the chemical composition of materials present is Energy Dispersive X-ray Spectroscopy (EDX).
Energy Dispersive X-Ray Spectroscopy (EDX)
In order to analyze the composition of the surface of components precisely, Mat-Tech utilizes Energy-Dispersive X-ray Spectroscopy (EDX). This is a surface analysis technique where an electron beam (emitting specific wavelengths of X-rays) strikes the component, thereby exciting an electron in an inner shell. This results in an electron hole in the electronic structure of the element.
The energy of the electron beam ranges from 10-20 keV. The amount of energy emitted in the form of X-rays depends on the element. The electron beam moves across the component, and the images are stored. The presence of Au, Ag, and Pd on the NP surface can be easily identified. However, elements with low atomic numbers are challenging to detect with EDX.
EDX can be used with very small components, even as small as a few cubic micrometers in size.