Evaluation of temperature effects in p-type silicon detectors

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 -1 and 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 -1 and 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.