Comparison of Ultrathin X-Ray Window Designs

Article type: Research Article

Authors: Viitanen, Veli-Pekka | Mutikainen, Risto | Nenonen, Seppo | Partanen, Panu

Affiliations: Outokumpu Instruments Oy, Riihitontuntie 7C, SF-02200 Espoo, Finland | Technical Research Centre of Finland, Semiconductor Laboratory, Otakaari 7B, SF-02150 Espoo, Finland

Note: [] To whom correspondence should be addressed.

Abstract: In order to fabricate entrance windows for soft x-ray detectors, various technologies have been developed. Depending on the x-ray-detector type and the environment in which the windows are used, entrance windows must meet several, often contradictory, requirements: while good pressure tolerance and durability as well as gas tightness require thicker structures, good x-ray transmission can only be achieved with thin membranes. In this paper, the suitability of different window types for various applications is discussed. The applicability discussion is based on the results of tests performed on prototype windows, as well as on calculated and measured x-ray transmission properties. A comparative study of endurance vs transmission properties of some candidate membrane materials is also presented. Test results include pressure tolerance and leakage rates as well as some measurements of radiation damage to the window materials. The window technologies presented include coated polyimide membranes with two different supporting schemes as well as submicrometer beryllium membranes.

DOI: 10.3233/XST-1993-4302

Journal: Journal of X-Ray Science and Technology, vol. 4, no. 3, pp. 182-190, 1994