Towards High-Resolution X-Ray Imaging Using a Structured Scintillator
2012 (English)In: IEEE Transactions on Nuclear Science, ISSN 0018-9499, E-ISSN 1558-1578, Vol. 59, no 1, 19-23 p.Article in journal (Refereed) Published
Structured scintillators, by light-guiding secondary emitted visible photons to a pixel in a CCD or CMOS image sensor, improve the lateral resolution of X-ray imaging detectors. In this work we have fabricated pore arrays in a silicon wafer and subsequently filled them with CsI(Tl) by a melting process. The goal was to down-scale the pore geometry for increased resolution. The results show that although pore depth must be reduced to comply with achievable aspect ratio of the Inductively Coupled Plasma (ICP) etching, melting into the pores is possible. The time and temperature has, however, to be optimized to prevent thallium loss during the melting. By correlating light yield measurements with the X-ray absorption in samples of various geometries, we find that the efficiency is slightly reduced for pore diameters approaching one micron. Nevertheless, the increased absorption in deep pores will lead to a significantly improved quantum efficiency compared to thin films currently used to achieve the same lateral resolution.
Place, publisher, year, edition, pages
2012. Vol. 59, no 1, 19-23 p.
Scintillation detectors, waveguides, X-ray imaging technologies
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-91260DOI: 10.1109/TNS.2011.2177477ISI: 000300422500003ScopusID: 2-s2.0-84857258040OAI: oai:DiVA.org:kth-91260DiVA: diva2:509100
QC 201203122012-03-122012-03-122012-03-12Bibliographically approved