Interaction of HfO2∕SiO2∕Si structures with deuterium gas

Abstract

Hf O 2 films (2.5 to 12 nm) deposited on thermal SiO2 (1.5 nm) on Si were annealed in deuterium gas at 400–600 °C and incorporated D amounts were quantified using the D(He3,p)He4 nuclear reaction. We found ∼1013Dcm−2 in the SiO2 interlayer region and up to 2.2×1014Dcm−2 near the HfO2 surface, whereas D amounts in the bulk of the HfO2 films were determined to be below 1013cm−2. However, analyses employing the H1(N15,αγ)C12 nuclear resonant reaction showed much more spurious H present in the bulk of HfO2 films. Mechanisms of D incorporation and desorption as well as contribution of the present results to the understanding of HfO2-based devices are discussed.