Characteristics of HfO₂ - Al₂O₃ laminate films containing incorporated N as a function of stack structure and annealing temperature

The properties of Al2 O3 -Hf O2 laminated films with incorporated N were investigated as a function of stack structure and annealing temperature by high-resolution x-ray photoelectron spectroscopy, and medium energy ion scattering (MEIS). The MEIS results indicate that the diffusion of Si from the Si substrate into film increased in the case where a film with a buffer layer of Al2 O3 was present during the annealing at temperatures up to 800 °C, while it led to a relative suppression in a film with a Hf O2 buffer layer. The incorporation of N was gradually increased in the film with a buffer layer of Al2 O3 on Si with annealing temperature, while the increase was abrupt in the film with a buffer layer of Hf O2 on Si at an annealing temperature of 900 °C. The N incorporated into the film was very unstable, resulting in out diffusion from the film after an additional annealing treatment.