Total Dose Response of Ge MOS Capacitors With HfO$_{2}$/Dy $_{2}$O$_{3}$ Gate Stacks

We report the results of total ionizing dose radiation tests on germanium-substrate MOS capacitors with HfO
₂
/Dy
₂
O
₃
gate dielectrics with effective oxide thicknesses of ~1.9 and 1.1 nm. There are significant densities of border traps before irradiation, and no measurable changes in device response after 10 Mrad(SiO
₂
) exposure. We attribute the lack of net oxide charge trapping to equal electron and hole trapping and/or charge neutralization via gate leakage current. The introduction of Dy
₂
O
₃
evidently leads to reduced charge trapping in these HfO
₂
/Dy
₂
O
₃
dielectrics relative to devices with only HfO
₂
.