Journal of X-Ray Science and Technology - Volume 8, issue 2

Authors: Heck, John M. | Attwood, David T. | Meyer-Ilse, Werner | Anderson, Erik H.

Article Type: Research Article

Abstract: Determining the resolution of a zone plate X-ray microscope is a complicated issue, depending on many factors in addition to the quality of the optic. These include the degree of coherence of the illumination, the illumination spectrum, and the nature of the resolution test object. In this paper, we examine closely how the degree of coherence of the illumination affects the resolution as measured with three typical test patterns. In addition, we determine the extent to …which the illumination spectrum affects the resolution. We compare X-ray microscope test images to numerical simulations as a function of coherence and illumination spectrum. We are able to conclude that in these experiments, the resolution of the X-ray microscope is 41 nm, or 40% discrepancy is due to aberrations in the objective zone plate lens. Show more

Citation: Journal of X-Ray Science and Technology, vol. 8, no. 2, pp. 95-104, 1998

Authors: Posey, Ralph | Brown, Denice | Broadwater, Keita | Swint, Tracy | Valentine, Jami | Ebert, Paul J.

Article Type: Research Article

Abstract: Images of small fluorescence X-ray sources obtained by diffraction with opaque spheres were recorded with a flow-proportional counter and on X-ray sensitive film. Image fluxes and intensities obtained experimentally were compared with theoretical estimates made using analytical expressions derived from the sphere's point-source imaging properties.

Citation: Journal of X-Ray Science and Technology, vol. 8, no. 2, pp. 105-116, 1998

Authors: Fazzio, R. Shane

Article Type: Research Article

Abstract: Circularly scanned-beam laminography is currently the predominant technique used for the nondestructive examination of printed circuit solder assemblies via cross-sectional X-ray imaging. Given industry trends towards double-sided assemblies and limited access components, cross-sectional X-ray inspection is furthermore becoming increasingly important. Use of X-rays for inspection of solder joints on loaded printed circuit boards nonetheless often leads to concern surrounding possible undesirable radiation effects on the circuitry mounted on the board. In this …paper we develop a simple analytical model useful for predicting the radiation exposure rates in a scanned-beam laminography system. We demonstrate the validity of the model through a series of dosimetry experiments. Show more

Citation: Journal of X-Ray Science and Technology, vol. 8, no. 2, pp. 117-133, 1998

Authors: Chakera, J.A. | Kumbhare, S.R. | Gupta, P.D.

Article Type: Research Article

Abstract: An experimental study is performed of soft X-ray emission from laser produced plasmas for single shot X-ray contact microscopic imaging of physical and biological microstructures. Planar copper targets are irradiated by 10J, 28 nS Nd:glass laser pulses in the intensity range of 1011 W/cm² to 3× 1012 W/cm². Measurements of keV X-ray emission viz. X-ray intensity scaling with laser intensity, X-ray source size, X-ray conversion efficiency and exposure dose on the sample are presented. Fine …copper grids of 70 mm mesh size and 10 mm thickness are used as test samples for imaging on ERP-40 photoresist. A spatial resolution of ~195 nm is observed, consistent with theoretical estimate considering the contribution of geometrical and diffraction blurring, and statistical noise of photons incident on the sample. This study should be useful in proper selection of source parameters for optimization of spatial resolution in single shot keV contact imaging. Show more

Citation: Journal of X-Ray Science and Technology, vol. 8, no. 2, pp. 135-143, 1998

Authors: He, Yejun | Chen, Jun | Li, Yude | Wei, Fuzhong | Wang, Dacun | Luo, Ping | Yan, Yiming

Article Type: Research Article

Abstract: The monolithic polycapillary X-ray Lens is a fast developing optics that has many applications in different fields, one of them, described in this paper, is a successful application in the X-ray diffraction for macromolecular crystallography. The direct beam intensity irradiating on crystal with usage of the monolithic X-ray lens was increased 1 to 2 order of magnitude more than the traditional method with the double focusing mirrors. the diffracted X-ray intensity was increased more than about …8 times, the resolution was improved by 0.20.6Å, and the signal to noise ratio was also improved. The measuring time became shorter. The crystal samples which had to be analyzed by synchrotron before are able to be investigated in routine laboratory now. Show more

Keywords: X-rays, monolithic polycapillary optic, macromolecular crystallography

Citation: Journal of X-Ray Science and Technology, vol. 8, no. 2, pp. 145-149, 1998