Radiation damage studies of amorphous-silicon photodiode sensors for applications in radiotherapy X-ray imaging
نویسنده
چکیده
The high radiation tolerance of hydrogenated amorphous silicon (a-Si : H) is one reason it has become a candidate for high-energy physics applications and for radiotherapy and diagnostic imaging. The performance of 1 [,m and 5 [Lm a-Si : H n-i-p photodiode sensors used in conjunction with Lanex (Gd 202S : Tb) intensifying screens has been measured as a function of high-energy photon dose . Over the course of irradiation with a Co source to a total dose of -104 Gy the output signal due to the sensor-screen combinations experienced maximum variations of -1.3% and +2.7% for the 1 [Lm and 5 Wm sensors, respectively. Transient effects associated with the sensors and screens are also reported .
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