Sequential Single-Oriented Growth of (111) Cu/(111) HfN/(002) Hf Trilayered Film on (001) Si and Its Thermal Stability

Abstract

We investigated the sequential single-oriented growth of Cu/HfN/Hf trilayered film on Si and the interfacial solid-phase reaction of the Cu/HfN/Hf/Si contact system by X-ray diffraction, Auger electron spectroscopy and X-ray photoelectron spectroscopy analyses. Sequential single-oriented growth of (111) Cu/(111) HfN/(002) Hf trilayered film was realized on (001) Si when a HfN (300 Å)/Hf (300 Å) bilayered film was interposed between Cu and Si. It was revealed that this contact system can tolerate temperatures of up to 520°C, which is much higher than the temperature (400°C) required for the conventional post-metallization process, maintaining a Hf3Si2 silicide adhesion layer with the lowest contact resistivity at the Si interface and a (111) Cu overlayer with excellent electromigration resistance.