An INCA Energy Dispersive X-ray Spectroscopy Detector (Oxford Instruments, Buckinghamshire, UK) is installed on the SEM.
Energy Dispersive X-ray Spectroscopy (EDS or EDX) is an analytical technique used for the elemental analysis or chemical characterization of a sample.
X-rays that are characteristic of an element's unique atomic structure are emitted when the electron beam removes an inner shell electron from the sample, causing a higher energy electron to fill the shell and give off energy. These characteristic x-rays are used to identify the elemental composition of the sample.
The Oxford INCA software package enables the user to carry out X-ray analysis to determine the elemental composition of the sample and generate a characteristic spectrum (such as the one seen above).