A Detailed Study on Zero-Bias Irradiation Responses of $\hbox {La}_{\text{2}}\hbox {O}_{\text{3}}$ MOS Capacitors

La
₂
O
₃
as a possible dielectric layer for a capacitor in MOS-based radiation sensors has been investigated under gamma irradiation doses up to 64 Gray. Capacitance-Voltage (C- V) and Conductance-Voltage (G/ω-V) characteristics including the series resistance (R
₅
) of the device have been studied. The La
₂
O
₃
thin-film crystal structures, phase identification, and the elemental compositions of the films were investigated by X-ray diffractometer and energy-dispersive X-ray spectroscopies. The density of the interface states (D
_it
) and fading characteristics were calculated following a series correlations to C-V and G/ω-V measurements. A desired linear flat band voltage shift-dose relation was obtained using the capacitance measurements. We observed that R
₅
barely decreases as irradiation dose increases, which has a crucial effects mainly on conductance of the device characteristics. Dit features were improved with irradiation doses but still in the order of 1010 eV
^-1
cm
^-2
. This did not cause any significant device degradation through its operation. Finally, the fading values of the devices with La
₂
O
₃
layers were found to be close to that of conventional SiO
₂
layers. The outcomes suggest that La
₂
O
₃
may be a promising future gate dielectric material candidate for radiation sensors in given radiation dose range.