Skip to main content Accessibility help
×
Home

X-Ray Optics for Scanning Fluorescence Microscopy and Other Applications

  • Richard W. Ryon (a1) and William K. Warburton (a2)

Abstract

Scanning x-ray fluorescence microscopy is analogous to scanning electron microscopy. Maps of the distribution of chemical elements are produced by scanning the specimen with a very small x-ray beam while collecting the XRF spectrum. Our goal is to perform such scanning microscopy with resolution in the range of <1 to 10 μm, using standard laboratory x-ray tubes. In order to increase the radiation flux on the specimen, we are investigating mirror optics in the Kirkpatrick-Baez (K-B) configuration, K-B optics uses two curved mirrors mounted orthogonally along the optical axis. The first mirror provides vertical focus, the second mirror provides horizontal focus. We have used two types of mirrors: synthetic multilayers and crystals. Multilayer mirrors are used with lower energy radiation such as Cu Kμ. At higher energies such as Ag Kct, silicon wafers are used in order to increase the incidence angles and thereby the photon collection efficiency. In order to increase the surface area of multilayers which reflects x-rays at the Bragg angle, we have designed mirrors with the spacing between layers graded along the optic axis in order to compensate for the changing angle of incidence. Likewise, to achieve a large reflecting surface with silicon, the wafers are placed on a specially designed lever arm which is bent into a log spiral by applying force at one end. In this way, the same diffracting angle is maintained over the entire surface of the wafer, providing a large solid angle for photon collection.

Copyright

References

Hide All
1. Gurker, N., “Imaging Techniques for X-Ray Fluorescence and X-Ray Diffraction”, Advances in X-Ray Analysis, Vol. 30, (1987), pp. 5365.
2. Nichols, Monte C., Boehme, Dale R., Ryon, Richard W., Wherry, David, Cross, Brian, and Aden, Gary, “Parameters Affecting X-Ray Microfluorescence (XRMP) Analysis”, Advances in X-Ray Analysis, vol. 30 (1987), pp. 4551.
3. Larsson, S., Engstrom, P., and Rindby, A., “X-Ray Capillary Microbeam Spectrometer”, Advances in X-Ray Analysis, Vol. 33, (1990), pp. 623628.
4. Carpenter, D. A., Taylor, M. A., and Holcombe, C. E., “Applications of a Laboratory X-Ray Microprobe to Materials Analysis”, Advances in X-Ray Analysis, vol. 32 (1989), pp. 115120.
5. Kumakhov, Muradin and Gibson, Walter, as reported in “Piping X-Rays Through a Glass Brightly”, Science, vol. 252 (12 April 1991), pp. 208209.
6. Niemann, B., Schmahl, G., et al., “X-Ray Microscopy with Synchrotron Radiation at the Electron Storage Ring BESSY in Berlin”, Nuclear Instruments and Methods in Physics Research A246 (1986), pp. 675680.
7. Bionta, Richard M., Skulina, Kenneth M., et al., “Tabletop X-ray Microscope Using 8 keV Zone Plates”, Optical Engineering, Vol. 29, No. 6 (1990), p 576.
8. Kirkpatrick, Paul and Baez, A. V., “Formation of Optical Images by X-Rays”, Journal of the Optical Society of America, vol. 38, No. 9 (1948), pp. 766774.
9. Underwood, J. H., Thompson, A. C., Wu, Y. and Giauque, R. D., “XRay Microprope Using Multilayer Mirrors”, Nuclear Instruments and Methods in Physics Research A266 (1988), pp. 296302.
10. The multilayer code we use is an adaptation by Barry Jocoby of the Lawrence Livermore National Laboratory of a code by Underwood and Barbee. See James H. Underwood and Troy W. Barbee, Jr., “Synthetic Multilayers as Bragg Diffractors for X-Rays and Extreme Ultraviolet : Calculations and Performance”, American Institute of Physics Conference Proceedings Number 75, Low Energy X-Ray Diagnostics-1981, pp. 170-178.
11. Cerrina, Franco, Lai, Barry, Chapman, Karen, Welnak, Chris, and Runkle, Paul, “Shadow Primer”, Center for X-Ray Lithography, University of Wisconsin, Madison, Wisconsin.

X-Ray Optics for Scanning Fluorescence Microscopy and Other Applications

  • Richard W. Ryon (a1) and William K. Warburton (a2)

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed