Hitachi S-4700
System Overview
The Hitachi S-4700 is a field emission scanning electron microscope (FE-SEM). More powerful than a standard SEM, the S-4700, under optimal conditions, can magnify images upwards of 500,000 times and resolve features to 2 nanometers. In addition, a cathodoluminescence detector, backscatter electron detector and energy dispersive x-ray spectrographic detector accompany the microscope.
Cathodoluminescence and Backscatter Electron Detectors
The S-4700 is equipped with a standard secondary electron detector (SE), a backscatter electron detector (BSD) and a Gatan MonoCL cathodoluminescence detector (CL). The BSD is sensitive to slight energy variations occurring when a high energy electron scatters off the nucleus of an atom. This sensitivity allows the BSD to map out variations in the densities of the sample. The CL measures photons released by the sample as it interacts with the electron beam and uses the information gathered from these photons to conduct elemental analysis.
Energy Dispersive X-ray Spectrographic Detector
In addition, the S-4700 includes a Bruker AXS Quantax 4010 Energy dispersive X-ray spectrometer (EDS). The EDS detector measures X-rays given off by sample as it is excited by the electron beam. Utilizing this data the Bruker software is capable of graphing the elemental make up of the sample, as well as creating a map of the image highlighting where selected elements appear. The Quantax 4010 is equipped with a Silicon Drift Detector (SDD) which can provide a high resolution and accurate map and/or graph of the sample in approximately an hour. Position tagged spectrometry allows for point specific analysis of all elements from atomic number 4 (beryllium) up to 95 (americium) contained in the sample to be detected and analyzed simultaneously.