Large Solid Angle X-Ray Detector for Electron Microscopy

One of the standard analytical tools on almost all electron microscopes (EM) is an energy dispersive x-ray spectroscopy (EDS) detector used for chemical analysis. However, there are many limitations with the current generation of EDS detectors for EM. The best potential for achieving larger detector active areas, superb energy resolution and an order of magnitude higher count rate compared with conventional EDS detectors, comes from a new detector technology - the silicon drift detector. We will develop a large solid angle detector (up to 0.8 srad), with low noise electronics, specifically for the high vacuum, demanding environments of the analytical EM. Phase I will include evaluation and selection of one of three preliminary spectrometer designs; Phase II will include optimization of the selected design, construction and full evaluation of the prototype spectrometer on the NIST analytical EM. COMMERCIAL APPLICATIONS: Energy dispersive x-ray spectrometers (EDS) are used on virtually all electron microscopes (EM), as well as in many other industrial and scientific applications. The market for EDS detectors on EMs is in the multi-million dollar range. The spectrometers developed here could also be used in process control in the metals and chemicals industries, in powder diffraction detectors in materials analysis, high performance x-ray detectors for synchrotron experiments, and contamination control in the semiconductor industry.