Lu2O3/Al2O3 gate dielectrics for germanium metal-oxide-semiconductor devices

Abstract

Effect of Ge out diffusion into Lu2O3 /Al2O3 high-k dielectric stack was investigated. Increasing Ge

signal intensity with increasing annealing temperature was observed, which suggests that there may be excessive Ge incorporation into the high-k film. The electrical measurement shows an

improvement of the k value with annealing temperature, as well as an increasing trend in the leakage

current density suggesting degradation in electrical performance due to Ge incorporation. Our work suggests that 8.8 at. % of Ge in the film is excessive and result in degradation of the electrical

performance of the device due to the increased leakage current.