RESIDUAL STRESS IN VERY THIN BARIUM STRONTIUM TITANATE FILMS
Abstract:Residual stress in thin film barium strontium titanate is thought to be preferentially distributed within the thickness of the film, such that a high degree of residual stress is manifested at the film-substrate interface, and the level of residual stress gradually decreases towards the free surface. To investigate this phenomena, a series of very thin films of barium strontium titanate with both cubic (30-70 Ba-Sr ratio) and tetragonal (80-20 Ba-Sr ratio) lattice structures were fabricated on platinized silicon and magnesium oxide. The thickness of these films was varied from 4-25 nm and the level of residual stress was investigated. The results highlighted within this paper, indicate that the cubic and tetragonal films manifest stress via different mechanisms, and that the substrate affected the magnitude of the residual stress but not the mechanism of stress relief.
Document Type: Research Article
Publication date: 2008-01-01