Effects of vacuum ultraviolet and ultraviolet irradiation on ultrathin hafnium-oxide dielectric layers on (100)Si as measured with electron-spin resonance

Abstract

The effects of vacuum ultraviolet (VUV) (7.2 eV) and UV (4.9 eV) irradiation on hafnium-oxide dielectric layers were studied with electron-spin resonance to detect defect states. Silicon dangling-bond defects (Pb centers) and positively charged oxygen vacancies (E′ centers) were detected with g-factor fitting. VUV irradiation increases the level of Pb states, while UV decreases the level of Pb states but increases the level of E′ states significantly. Rapid thermal annealing appears to mitigate these effects. Absolute values of the defect-state concentrations are presented.