Study of gamma irradiation effect on electrical properties of MOSFET and MOS diode for application in dosimetry

In this work, the effect of the gamma radiation on the threshold voltage of metal oxide field effect transistor (MOSFET) was investigated. First, the purchased P typeMOS transistor was considered. Due to a nonlinear response to the administrated dose, the different regions were analyzed. Then we constructed an Al/n-Si/SiO2/Al MOS diode. These diodes were irradiated to mili to kilo Gray dose and their electrical behavior were investigated. In forward bias, the current variation was low but in reverse bias and lower than -20 volt, the current variation was large and measurable. A non-constant responsivity was obtained for diodes which is due to the non linearity of dose - current curve. Three different regions were chosen and the responsivity in these regions was obtained.