 |
 Scanning Electron Microscope (SEM)
Contact: Dr. Donggao Zhao, phone: 512-471-1177 (O)Location GEO 5.110
OverviewInstalled in 1990, our SEM has three detector systems. In secondary electron (SE) imaging mode magnifications from approximately 50x to 150,000x are available. The Tracor energy dispersive X-ray detector (EDS) provides qualitative analysis of major elements with atomic number equal to or greater than 11 (Na). The third detector is an Oxford Instruments cathodoluminescence (CL) detector that has been modified in-house with color filters to permit acquisition of close-to-true color images. Image recording in SE or CL modes can be done with either Polaroid film or digitally using digital beam control by 4pi.
TrainingSamplesA wide range of sample types can be examined in our SEM. All samples must have a conductive coating applied to their surface, either sputtered gold or evaporated carbon. Samples must contain no volatiles (water is the main concern, but some oil-saturated samples might also be unsuitable, for example). Typical samples are small enough to be mounted on 1-cm diameter Al-cylinders. Four such samples can be loaded at the same time. Somewhat larger samples, up to a few cm on a side, can also be used, depending upon whether they fit through the airlock and pose no possibility of colliding with the detectors. CL imaging requires polished thin sections or rock slabs.
|
|
 |
.GIF){kind=small}