The radiation response of hafnium oxide based metal-oxide-semiconductor capacitors under 60Co gamma ray

Radiation induced oxide and interface trapping characteristics in Al/HfO
₂
/Si MOS capacitor under
⁶⁰
Co gamma ray are studied in this article. We discovered positive oxide trapped charge in the HfO
₂
/Si system after gamma-irradiation with different total dose. Post-annealing process can reduce the radiation induced trapped charge density in the HfO
₂
/Si system, and SiO
₂
layer between HfO
₂
and Si can greatly reduce the interface trapped charge density. Moreover, we discovered that oxygen vacancy is the dominant radiation induced defect in bulk HfO
₂
, and silicon dangling bond and silicon suboxide are main interface defects related to the radiation induced interface trapping.