The effect of Y/sub 2/O/sub 3/ buffer layer for La/sub 2/O/sub 3/ gate dielectric film

La/sub 2/O/sub 2/, Y/sub 2/O/sub 3/ and La/sub 2/O/sub 3//Y/sub 2/O/sub 3/ stack dielectric films were deposited on silicon by electron-beam evaporation. Chemical and electrical analyses of the interfacial growths of these films with silicon after heat treatment are performed comparatively. X-ray photoelectron spectroscopy (XPS) analysis reveals that Y/sub 2/O/sub 3/ layer suppresses the formation of SiO/sub 2/ at the interface. The Y/sub 2/O/sub 3/ layer also reduces the hysteresis in capacitance-voltage characteristics and leakage current without changing the equivalent oxide thickness (EOT).