Room temperature interactions of water vapor with HfO ₂ films on Si

Abstract

Hf O2 Si O2 Si (001) thin film structures were exposed at room temperature to water vapor isotopically enriched in H2 and O18 followed by quantification and profiling of these nuclides by nuclear reaction analysis. We showed (i) the formation of strongly bonded hydroxyls at the Hf O2 surface; (ii) room temperature migration of oxygen and water-derived oxygenous species through the Hf O2 films, indicating that Hf O2 is a weak diffusion barrier for these oxidizing species; (iii) hydrogenous, water-derived species attachment to the Si O2 interlayer, resulting in detrimental hydrogenous defects therein. Consequences of these results to Hf O2 -based metal-oxide-semiconductor devices are discussed. © 2006 American Institute of Physics.