Localized degradation and breakdown study of cerium-oxide high-к gate dielectric material using scanning tunneling microscopy

In this work, we use scanning tunneling microscopy (STM) to study the localized degradation, breakdown and post-breakdown of a high-κ (HK) gate dielectric material, cerium oxide (CeO
₂
) deposited directly on a silicon substrate. The novelty of the study lies in analyzing the breakdown phenomenon from a macroscopic metal-oxide-semiconductor (MOS) capacitor level to a very localized nanoscale breakdown location. The physics of failure for these polycrystalline cerium oxide HK films is also discussed.