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

Abstract

We report the results of total ionizing dose radiation tests on germanium-substrate MOS capacitors with HfO2/Dy2O3 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(SiO2) 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 Dy2O3 evidently leads to reduced charge trapping in these HfO2/Dy2O3 dielectrics relative to devices with only HfO2.