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We describe preparation and properties of GdScO3 thin films. The films were prepared by liquid injection metal-organic chemical vapor deposition, MOCVD at 600 ºC on (100) Si substrate. The as-deposited films were amorphous with a smooth surface and sharp GdScO3/Si interface. X-ray diffraction showed that the amorphous phase is well preserved upon rapid thermal annealing up to 1000 ºC. However, modification of the X-ray reflectivity pattern after annealing at 1000 ºC indicates increasing of the film thickness, presumably due to diffusion of silicon from the substrate into the whole volume of the film. Capacitance-voltage measurement resulted in dielectric constant of 22. It is shown, that exact stoichiometry of GdScO3 is not necessary to achieve dielectric constant above 20.

Capacitance-voltage characteristics of Ru/Hf x Si 1-x O y /Si gate stacks with Hf x Si 1-x O y composition Hf/Si = 75/25 and Hf/Si = 50/50 were analyzed. The characteristics revealed a high density of negative fixed charges N ox as -5 X 10 12 cm -2 in the oxide film. We have observed that the value of the Ru work function remained constant after forming gas annealing at temperatures between 430 and 510°C, respectively, while fixed charges were reduced at temperatures above 470°C. We speculated that the decrease of negative fixed charges can be explained by the generation of positively charged [Si 2 = OH] + centers in the oxide layer. The positively charged centers can account for a compensation of the negative fixed oxide charge. Rapid thermal annealing at temperatures up to 800°C in nitrogen did not influence the fixed oxide charges in the Hf x Si i-x O y films.