Dosimetry aspects of hafnium oxide metal-oxide-semiconductor (MOS) capacitor

This paper reports the investigation of hafnium oxide based metal-oxide-semiconductor capacitor for the detection of gamma radiation. The fabrication of the device involved deposition of hafnium oxide thin film on n-type Si wafer by electron beam evaporation technique followed by deposition of aluminum metal layer by thermal evaporation process. The device was irradiated incrementally to the cumulative dose of 480 Gy by gamma rays of 1.25 MeV (Co-60). The change in accumulation capacitance, effective oxide charge and interface trap density with cumulative gamma dose was examined at room temperature. As the creation of oxide charge and change in oxide capacitance are well correlated with radiation dose, the device can be useful for radiation dosimetry.