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In the recent decade, pixelated CsI(Tl) scintillation films are developed for X-ray imaging to improve spatial resolution. Several methods have been reported but better performance is still required. In this work, CsI(Tl) films were prepared on specially designed patterned substrates with regular arrays of pits. Each CsI(Tl) micro-column locates in one pit. In this way, CsI(Tl) films with pixel-like columnar-matrix structure were achieved. Each pixel contains one micro-column and the size of pixel is the average diameter of the columns. Morphologies of the films were examined by scanning electron microscopy. Imaging performances of films dependent on their structure are discussed. The prepared CsI(Tl) films show superior image performance and may be well-coupled with pixelated photo sensors for X-ray imaging systems.

CsI:Tl scintillation films were prepared on the net-like patterning substrates. The pattern of the substrates as well as the morphology of the CsI:Tl films were measured by SEM. The results show that the size of each grid on substrate is 55μm which is formed by SU-8 photoresist with 5μm in both height and width, and the CsI:Tl films display quite a good columnar structure. The spatial resolutions of X-ray imaging were taken by MTF measurement. The spatial frequency of the CsI:Tl films on patterned substrates can reach up to 10 lp/mm at the 10% level of MTF, which is twice higher than that of the CsI:Tl film on the substrate without patterning.

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