Capability of Semiconducting NiO Films in Gamma Radiation Dosimetry

Electrical properties of RF magnetron sputtered p-NiO films were characterized after fabrication and after gamma irradiations using $\text{}^{137}Cs$ and $\text{}^{60}Co$ sources. Electrical parameters are obtained from the Hall measurements, impedance spectroscopy and C-V measurement of n-Si/p-NiO junction diodes. The results show that resistivity of the NiO film is gradually increased following after sequential irradiation processes because of the decrease in holes' concentration. Hole concentration of a NiO film decreases from the original value of $4.36 \times 10^{16} cm^{-3}$ to $2.86 \times 10^{16} cm^{-3}$ after $\text{}^{137}Cs γ$ irradiation with doses of 10 Gy. In the case of γ irradiation from $\text{}^{60}Co$ source, hole concentration of the film decreases from $6.3 \times 10^{16}//cm^3$ to $4.1 \times 10^{16}//cm^3$ and to $2.9 \times 10^{16}//cm^3$ after successive expositions with a dose of 20 Gy.