Scanning Electron Microscopy Lab

The University of Denver has a JEOL 5800LV scanning electron microscope (SEM) equipped with secondary and backscatter electron detectors, and an X-ray detector for energy dispersive spectroscopy (EDS).  The instrument can operate at low vacuum (<2 torr) for analysis of uncoated and biological samples.  It has a large specimen chamber and ample stage motion to examine specimens as large as 7 inches in diameter.

Secondary Electron Detector

For each high energy electron striking the surface, usually many low energy secondary electrons are given off the surface.  The secondary electron detector sweeps up these electrons and forms an image based on the number of secondary electrons.  The secondary electron detector gives the best resolution and it is the mostly commonly used detector.

Backscatter Electron Detector

A backscattered electron is an electron that scatters off the nucleus of an atom.  The larger the nucleus of the atom, the more electrons are backscattered.  As a result, the backscatter electron detector gives good compositional contrast.  If the compositional information from the detector is subtracted off, the result is a surface topography image.

Energy Dispersive X-ray System

The Oxford Pentafet energy dispersive X-ray detector (EDS) is available for qualitative and semi-quantitative elemental analysis.  The EDS detector has an ultra-thin window that allows for element detection of carbon and higher atomic number elements.  An elemental or X-ray map of the surface can also be obtained using this detector.

Department of Engineering, University of Denver,

2390 S. York St., Denver, CO  80208 (303) 871-3580