Higher-k LaYOx films with strong moisture resistance

The permittivities and the moisture resistance of LaYOx films annealed at 600 degrees C with different Y concentrations are investigated. The permittivities of 40%Y-LaYOx and 70%Y-LaYOx films are higher than 25. The high permittivities come from the well crystallized hexagonal phase of LaYOx films, since the hexagonal phase rare earth oxides show higher permittivity than the cubic phase ones due to the smaller molar volume of the hexagonal phase. Furthermore, the high permittivity LaYOx films (40%Y-LaYOx and 70%Y-LaYOx) show a strong resistance to the moisture due to the introduction of Y2O3. (c) 2006 American Institute of Physics.