Impact of texturing on the phase transitions in sol–gel‐processed Bi(Sm)FeO3 thin films on LaNiO3‐buffered silicon.

The orientation modulation of ferroelectric materials is a suitable method to optimize material performance. Textured Bi1‐xSmxFeO3 thin films (near the rhombohedral‐orthorhombic (R‐O) phase boundary, that is, x = 0, 0.1, 0.12, 0.14, and 0.16) were fabricated using the sol‐gel process by introducing a LaNiO3 (LNO) seed layer. Structural and ferroelectric characterizations were used to investigate the effect of texturing on the Sm doping‐induced R‐O phase transition of the BiFeO3 thin films. It was found that a phase transition occurred from the rhombohedral to the orthorhombic structure with increasing Sm content in the nontextured polycrystalline films, resulting in an R‐O phase boundary at x = 0.12. In contrast, the R‐O phase boundary in the textured films was more diffuse, indicating a two‐phase coexistence in a boarder range of Sm doping levels (x = 0.12‐0.16). This discrepancy was attributed to the complexity of the stress status in thin films. The dielectric and electrical properties of the nontextured and textured samples were investigated. The current study shows that the phase boundary in ferroelectric thin films can be altered by diverse means, thus providing insights into potential applications. [ABSTRACT FROM AUTHOR]