Fabrication and performance characteristics of a CsI(Tl)/PIN diode radiation sensor for industrial applications

CsI(Tl)/PIN diode radiation sensors were fabricated for application in various fields such as an NDT and an environmental radiation monitoring system. CsI(Tl) crystals of 11x11x21mm(3) were processed as optical grade from a CsI(Tl) ingot and matched with PIN diodes in consideration of the light loss and the external impact. The photodiode signal is amplified by a low-noise preamplifier and a pulse shape amplifier. At room temperature, the fabricated CsI(Tl)/PIN diode radiation sensors demonstrate an energy resolution of 7.9% for 660keV gamma rays and 4.9% for 1330keV. The fluctuation of the directional dependency was below 14% from 0 to 90 degree for the incident 660keV gamma rays. The compactness, the low-voltage power supply and the physical hardness are very useful features for industrial applications of the fabricated CsI(Tl)/PIN diode sensor.