A theoretical investigation concerning sensitivity variations in semiconductor detectors used in the short-circuit mode at different temperatures and pre-irradiation dose levels has been compared with experimental results. Initially, a sensitivity drop of more than 15 kGy-1and a sensitivity increase with temperature of less than 1 per 10 degrees C was found for p-type silicon detectors. After a pre-irradiation dose of 5 kGy with 20 MeV electrons these values were changed to about 6.5 kGy-1and 3 per 10 degrees C, respectively. As a temperature rise of about 10 was obtained in the detector when applied to a patient, the change in sensitivity has to be taken into consideration when the detector is used in patient dosimetry.
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