Electron Microscopy Analysis
Electron microscopy is a powerful tool for the analysis of materials and has a wide array of applications ranging from failure analysis, fundamental research and materials characterisation. Electron microscopy is often used to inspect fine details of objects as small as a few atoms in size, allowing for detailed analysis.
Scanning electron microscopy (SEM) is a very useful technique for analysing the surface of a material or device. The process involves passing an electron beam produced by an electron gun over the surface of the sample. This produces a two-dimensional image of the sample surface, with high resolution. The image can be used to analyse the surface topography of the sample, as well as its composition.
The advantages of SEM are its ability to produce high-resolution images and its high speed. It also has the ability to perform automated analyses, allowing for efficient and accurate analysis of the sample. Another advantage is the limited sample preparation necessary. A sample typically needs to be thinned, mounted on a holder and subjected to a vacuum. The process can easily be automated and does not require complex equipment.
Transmission electron microscopy (TEM) is a tool for examining thin foils of material. In TEM, a beam of electrons is passed through a thin sample, which can be down to a few hundred nanometers in thickness, and a resulting image is obtained on a fluorescent screen or with a digital camera.
The main advantage of TEM is its ability to produce high-resolution images of thin samples. This makes it ideal for examining samples with fine structures or structures at a nanometer scale. It is also possible to analyse the chemical composition of the sample with TEM, by observing the contrast seen in an image of the sample.
The main disadvantage of TEM is its time consuming nature, as it requires careful alignment and each observation needs to be performed in a vacuum. It also requires that the sample is thinned to a very small thickness and the sample holder must be very stable.
Both SEM and TEM are powerful analysis tools and can be used complementary to each other to provide even more information about a sample. By combining these two techniques it is possible to analyse a sample on different scales, from the surface properties to internal structures, as well as the chemical composition.
In conclusion, electron microscopy analysis is a powerful tool for the analysis of a variety of materials. It has the ability to provide high-resolution images, allowing detailed analyses of the sample. SEM and TEM, two different types of electron microscopy, can be combined and used to gain further information about a sample.
