Characteristics of Nickel Oxide Modified Zr-Doped HfO2 High-k Thin Films

Abstract

The effect of inclusion nanocrystalline nickel oxide in the ZrHfO high-k gate dielectric on the characteristics of the MOS capacitor has been investigated. The inclusion of a small amount of nanocrystalline nickel oxide effectively reduced the defect density in the bulk high-k stack and increased the breakdown voltage. After the gate dielectric breakdown, the charge retaining capacity of the capacitor with the ZrHfO dielectric was lost. However, the charge retention capacity of the capacitor with the nanocrystalline nickel oxide embedded dielectric was maintained, i.e., with the relaxation current flowing in the same direction as that before breakdown. Therefore, the embedding of nanocrystalline nickel oxide affected the performance and reliability of the ZrHfO high-k thin film.