We investigated the microstructures and electrical properties of [formula omitted] films deposited by reactive dc magnetron sputtering on Si substrates for gate dielectrics applications. We observed that the refractive index value of the [formula omitted] films increased with an increase in deposition powers and annealing temperatures. The [formula omitted] films deposited at elevated temperatures are polycrystalline, and both the monoclinic and tetragonal phases exist in the films. Films with higher density and improved crystallinity are obtained at higher deposition temperatures. The interfacial oxide layer between [formula omitted] films and Si substrates grew upon annealing in the [formula omitted] gas ambient, which is due to the oxidation of Si substrates by the diffusion of oxidizing species from [formula omitted] gas ambient. The accumulation capacitance value increased upon annealing in the [formula omitted] gas ambient due to the densification of the films, while it decreased in [formula omitted] gas ambient due to the growth of the interfacial oxide layer.
|Number of pages||5|
|Journal||Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films|
|Publication status||Published - 2001 Jul|
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films