Thermal stability and electrical characteristics of ultrathin hafnium oxide gate dielectric reoxidized with rapid thermal annealing

TLDR: In this article, the dielectric properties of ultrathin hafnium oxide reoxidized with rapid thermal annealing (RTA) have been investigated and the leakage current was found to be less than 3×10−2 ǫA/cm2 at −1.5 V (i.e., ∼2 V below VFB).

Abstract: Dielectric properties of ultrathin hafnium oxide reoxidized with rapid thermal annealing (RTA) have been investigated. Capacitance equivalent oxide thickness (CET) of 45 A hafnium oxide was scaled down to ∼10 A with a leakage current less than 3×10−2 A/cm2 at −1.5 V (i.e., ∼2 V below VFB). Leakage current increase due to crystallization was not observed even after 900 °C rapid thermal annealing (RTA), but CET did increase after high temperature RTA due to the interfacial layer growth and possible silicate formation in the HfO2 film.