Microstructure evolution and dielectric properties of Ba0.7Sr0.3TiO3 parallel plate capacitor with Cr interlayer

The microstructure, crystalline phase, surface morphology, and dielectric properties of a sandwich structure of Ba0.7Sr0.3TiO3/Cr/Ba0.7Sr0.3TiO3 (BST/Cr/BST) dielectric are characterized to understand the influence of the nano-Cr interlayer. BST dielectrics inserted with Cr film of thickness ranged from 2 nm to 15 nm all show the crystalline cubic phase. However, TiO2 layer is formed on the upper BST layer after the BST/Cr/BST dielectrics are annealed at 800 °C in O2 atmosphere for one hour. In this study, TEM, AFM, SEM, X-ray diffraction, and AES are employed to investigate the microstructure evolution of the BST/Cr/BST dielectrics after annealing. The correlations between the microstructure and the dielectric properties of the Pt/BST/Cr/BST/Pt capacitors with various Cr thicknesses are explored.