Influence of temperature and electrical modes on radiation sensitivity and errors of RADFETs

Influence of temperature and electrical modes on sensitivity and errors of ionizing radiation dose senor based on n- MOSFET (called as RADFET) have been investigated. There were measured the circuit's output voltages being equal to the gate voltage of RADFET-based dosimeter as function of the radiation doses at const values of the drain current and the drain - source voltage (conversion functions), as well as the current - voltage characteristics before, during and after irradiations at different temperatures. We showed how conversion functions, radiation sensitivities and errors are depending on the temperature and electrical modes. It is found that the conversion functions) have two characteristic regions for low and high doses (with negative and with positive radiation sensitivities). To interpret experimental data there were proposed the models of conversion function, its components and errors taking into account the separate contributions of charges in the dielectric and in SiO2-Si interface. Proposed models interpreting the experimental data can be used to predict performances of RADFET-based dosimeters.