Improvement of zirconium-doped hafnium oxide high-k dielectric properties by adding molybdenum

Dielectric properties of the Zr-doped hafnium oxide high-k thin film were improved with the addition of a small amount of molybdenum. The addition of molybdenum reduced the interface density of states and the oxide charge trapping density due to the removal of some oxygen vacancies and Hf dangling bonds in the film. It also decreased the leakage current and increased the breakdown voltage because of the increase of the total film thickness. The barrier height between the gate electrode and the high-k film was lowered as a result of the formation of a dipole layer at the interface. Therefore, the addition of a small amount of metal is an effective method to improve the dielectric properties of the high-k film.