Radiation-induced changes in the electrical properties of TiO2 thick films

The electrical properties of screen-printed TiO2 based thick films were explored in terms of gamma radiation influence. Screen-printed pn-heterojunctions and resistors were exposed to γ- radiation from a 137Cs source with an activity of 370 kBq. To form the resistors, a doping of TiO2 paste with 2 wt.% of Carbon was implemented to improve their conductivity. All samples showed an increase in the values of current with increasing radiation dose. The diode-type structures sustained a dose of 513 μSv, with considerable increase in leakage current values. Counterpart resistor-type structures experienced a three-order of magnitude increase in the values of current after irradiation with a dose of 7.524 mSv. Furthermore, S-type switching, followed by a forming effect were monitored at this stage, clearly attributed to the influence of gamma radiation.