Jg. Rocha et Jh. Correia, A high-performance scintillator-silicon-well X-ray microdetector based on DRIE techniques, SENS ACTU-A, 92(1-3), 2001, pp. 203-207
This paper proposes an X-ray detector based on an array of scintillator cry
stals, CsI:Tl, encapsulated in a wen that is etched into a silicon substrat
e by deep reactive ion etching. The X-ray energy is first converted to visi
ble light which is detected by a photodetector in the well bottom. DRIE tec
hniques are used to achieve perfect vertical side-walls 515 mum deep, 100 m
um pixel square size and to maximize the fill factor. The inner walls of th
e well that are coated with aluminum for improving the number of photons wh
ich arrives to the detector and for reducing cross-talk between adjacent we
lls. Simulations and modeling show an improvement of approximately 26% in t
he detection efficiency using an aluminum layer. (C) 2001 Elsevier Science
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