Scanning Electron Microscope (SEM)
In electron microscope an electron beam is used to “illuminate” an object. Electrons have a much smaller wavelength than light. As a result they can resolve much smaller structures. The smallest wavelength of visible light is about 40 millionths of a meter(250 nm). The wavelength of electrons used in electron microscopes is usually about 50 trillionths of a meter(0.2 nm). Images are produced by scanning an electron beam over the sample and measuring the electronic interactions with that surface. Electrons can be focused to a very small point (smaller than light can), and thus SEM can produced very high resolution images. At present we are having two Scanning Electron Microscopes and one of it equipped one with Energy Dispersive X-ray Analysis Unit. EDAX is a widely used technique to analyze the chemical components in a material under SEM. This method detects the X-rays produced as the result of the electron beam interactions with the sample. Mapping of the distribution of the different chemical elements constituting the specimen can be obtained.
X-ray data is processed to obtain the percentage of each measured element present in the individual particles. The compositional and morphological data are then combined for exploratory data analysis. SEM-EDAX are routinely used to obtain morphological information and identification of chemical composition of specimens of various branches of Sciences
- Scanning Electron Microscope (SEM)
- SEM Hitachi- S520, Japan; EDAX, INCA-X-Sight ,Oxford Link ISIS-300, UK
- SEM Hitachi S-3000N
- Magnification: 20 x to 3,00,00 x(SEM)