Monte Carlo Studies on the Amorphous Silicon Based Digital X-Ray Imagers


Results of Monte Carlo simulations on amorphous silicon based x-ray imaging arrays are described. In order to investigate the characteristics of amorphous silicon x-ray imaging devices and to provide the optimum design parameters, Monte Carlo simulations were performed. Monte Carlo simulation codes for our purpose were developed and various combinations of x-ray peak voltages, aluminum filter thicknesses, CsI(Tl) thicknesses, and amorphous silicon photodiode pixel sizes were tested in connection with detection efficiency and spatial resolution of the amorphous silicon based x-ray imager. With usual CsI(Tl) thickness of 300 µm to approximately 500 µm, detection efficiency was in the range of 70% to approximately 95% and energy absorption efficiency was in the range of 40% to approximately 70% for 60 kVp to approximately 120 kVp x-rays. From the simulations it was found that amorphous silicon pixel size and CsI(Tl) thickness were the most important parameters which determine the resolution of the imager. By use of our simulation results we could provide proper combinations of CsI(Tl) thicknesses and pixels sizes for optimum sensitivity and resolution.

Meeting Name

Proceedings of the 1997 IEEE Nuclear Science Symposium


Nuclear Engineering and Radiation Science

Document Type

Article - Conference proceedings

Document Version


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© 1997 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Jan 1997