Back
 MSA  Vol.9 No.2 , February 2018
Characteristics of the CsI:Tl Scintillator Crystal for X-Ray Imaging Applications
Abstract: Scintillators are high-density luminescent materials that convert X-rays to visible light. Thallium doped cesium iodide (CsI:Tl) scintillation materials are widely used as converters for X-rays into visible light, with very high conversion efficiency of 64.000 optical photons/MeV. CsI:Tl crystals are commercially available, but, the possibility of developing these crystals into different geometric shapes, meeting the need for coupling the photosensor and reducing cost, makes this material very attractive for scientific research. The objective of this work was to study the feasibility of using radiation sensors, scintillators type, developed for use in imaging systems for X-rays. In this paper, the CsI:Tl scintillator crystal with nominal concentration of the 10-3 M was grown by the vertical Bridgman technique. The imaging performance of CsI:Tl scintillator was studied as a function of the design type and thickness, since it interferes with the light scattering and, hence, the detection efficiency plus final image resolution. The result of the diffraction X-ray analysis in the grown crystals was consistent with the pattern of a face-centered cubic (fcc) crystal structure. Slices 25 × 2 × 3 mm3 (length, thickness, height) of the crystal and mini crystals of 1 × 2 × 3 mm3 (length, thickness, height) were used for comparison in the imaging systems for X-rays. With these crystals scintillators, images of undesirable elements, such as metals in food packaging, were obtained. One-dimensional array of photodiodes and the photosensor CCD (Coupled Charge Device) component were used. In order to determine the ideal thickness of the slices of the scintillator crystal CsI:Tl, Monte Carlo method was used.
Cite this paper: Pereira, M. , Filho, T. , Berretta, J. and de Mesquita, C. (2018) Characteristics of the CsI:Tl Scintillator Crystal for X-Ray Imaging Applications. Materials Sciences and Applications, 9, 268-280. doi: 10.4236/msa.2018.92018.
References

[1]   Nikl, M. (2006) Scintillation Detectors for X-Rays. Measurement Science and Technology, 17, 37-54.
https://doi.org/10.1088/0957-0233/17/4/R01

[2]   Kozyrev, E.A., Kuper, K.E., Lemzyakov, A.G., Petrozhitskiy, A.V. and Popov, A.S. (2016) Performance and Characterization of CsI:Tl Thin Films for X-Ray Imaging Application. Physics Procedia, 84, 245-251.
https://doi.org/10.1016/j.phpro.2016.11.042

[3]   Dong, F.Z., Peng, J., Kai, Z.H., Zhen, Z.B., Bo, Q.X., Feng, W.C., Yu, L. and Long, W. (2015) Performance Assessment of CsI(Tl) Screens on Various Substrates for X-Ray Imaging. Chinese Physics C, 39, 78202.
https://doi.org/10.1088/1674-1137/39/7/078202

[4]   Knoll, G.F. (2010) Radiation Detection and Measurement. 4th Edition, John Wiley & Sons, New York.

[5]   Zhao, W., Ristic, G. and Rowlands, J.A. (2004) X-Ray Imaging Performance of Structured Cesium Iodide Scintillators. Medical Physics, 31, 2594-2605.
https://doi.org/10.1118/1.1782676

[6]   Cha, B.K., Lee, D.H., Kim, B., Seo, C.W., Jeon, S. and Huh, Y. (2011) High-Resolution X-Ray Imaging Based on Pixel Structured CsI:Tl Scintillating Screens for Indirect X-Ray Image Sensors, Journal of the Korean Physical Society, 59, 3670-3673.
https://doi.org/10.3938/jkps.59.3670

[7]   Hormozan, Y., Sychugov, L. and Linnros, J. (2016) High Resolution X-Ray Using a Structured Scintillator. Medical Physics, 43, 696-701.
https://doi.org/10.1118/1.4939258

[8]   Mesquita, C.H. and Hamada, M.M. (2007) Development of Monte Carlo simulation to Study Linear Radiation Position Sensitive Detectors. IEEE Nuclear Science Symposium Conference Record, Honolulu, 26 October-3 November 2007, 871-875.
https://doi.org/10.1109/NSSMIC.2007.4436467

[9]   Bridgman, P.W. (1925) Certain Physical Properties of Single Crystals of Tungsten, Antimony, Bismuth, Tellurium, Cadmium, Zinc, and Tin. Proceedings of the American Academy of Arts and Sciences, 60, 303-383.

[10]   Garapyn, I., Hud, I. and Pavlyk, B. (2004) Properties of Cesium Iodide Prepared by Different Purification Methods. Radiation Measurements, 38, 475-479.
https://doi.org/10.1016/j.radmeas.2004.01.014

[11]   Margulies, M., Witomski, P. and Duffar, T. (2004) Optimization of the Bridgman Crystal Growth Process. Journal of Crystal Growth, 266, 175-181.
https://doi.org/10.1016/j.jcrysgro.2004.02.043

[12]   Pereira, M.C.C. and Filho, T.M. (2013) Inorganic Scintillators of Li+ Doped CsI for Neutron Detection. International Nuclear Conference (INAC 2013), Recife, 24-29 November 2013.

[13]   US Joint Committee on Powder Diffraction Standards. Selected Standard X-Ray Diffraction Powder, Vol. 4, 47.

 
 
Top