Influence of electrical modes on sensitivity of MISFET ionizing radiation dose sensors

摘要

The influence of electrical modes on the radiation sensitivity of the sensors based on the metal-silicon dioxide-semiconductor field-effect transistor (RadFET) was experimentally investigated. The RadFETs were fabricated by means of conventional MOS-technology. There were measured the RadFET-based microdosimeter output voltages V_(out) as function of the X-rays radiation doses D for different drain currents I_D and source-drain voltages V_D. It was shown how the conversion function V_(out)(D) and the radiation sensitivity S_D are depending on electrical modes. To interpret experimental data there were presented the models based on calculations the dependences of threshold voltage V_T and specific slope (transconductance) b vs. D. These dependences were calculated from the experimental I_D-V_G characteristics measured before, during and after irradiations (value V_G is the gate voltage).