Radiation therapy treatment unit dose-rate effects on metal–oxide–semiconductor field-effect transistor (MOSFET) detectors
نویسندگان
چکیده
Metal oxide semiconductor field effect transistor (MOSFET) detectors have recently been introduced to radiation therapy. However, the response of these detectors is known to vary with dose rate. Therefore, it is important to evaluate how much variation between the treatment prescribed dose and the dose that is actually delivered to the patient using high-energy photon or electron beams under conditions of different dose rates can be attributed to the detector. The aim of this study was to investigate MOSFET dependence on different dose-rate levels. The measurements were done by exposing the mobile MOSFET detectors to a dose of 100 cGy using a linear accelerator with energy of 6 MV and different dose rates from 100 cGy/MUs to 600 cGy/MUs.The results showed that the dose rate dependence of a MOSFET dosimeter was within ±1.0%. MOSFET detectors are suitable for dosimetry of photon beams, since they showed excellent linearity with dose rate variation.
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