Auger Electron Spectroscopy Study on the Characterization and Stability of the Cu₉Al₄/TiN/Si System

Diffusion barrier properties of TiN films to silicon and the Cu 9 Al 4 compound have been studied using Auger electron spectroscopy. The experimental results indicate that the TiN layer of 800 Å is effective as a diffusion barrier at 670°C. It is found that the reaction of Al in the compound with Ti in the barrier results in the failure of the system due to intermixing of elements at 700°C. The failure temperature of 700°C, which is higher than that of aluminum or copper metallization, is due to the stability of the Cu 9 Al 4 compound itself.