Low□temperature preparation of baxsr1-xtio3 thin films prepared by sol-gel-hydrothermal method

Abstract

BaxSr1-xTiO3 (BST) thin films with perovskite structure have been prepared on /Pt/Ti/SiO2/Si substrate using a combined process of conventional sol-gel process and a hydrothermal treatment. Atomic ratio in the film, Ba/Sr, was controlled by changing the concentration ratio of Ba(OH)2 and Sr(OH)2 of work solution. The BST thin films with polycrystalline structure are obtained on silicon at processing temperature of 140°C. The structure development, stoichiometry, spectroscopic, and dielectric properties of BST thin films have been systematically investigated. X-ray diffraction patterns show that well-developed crystallites with a pure perovskite phase have been formed. The composition of BST thin film derived by sol-gel-hydrothermal treatment depends on the concentration ratio of Ba(OH)2 and Sr(OH)2 of work solution intensively. SEM and AFM results show that the structure of as-treated BST thin film strongly depends on the film thickness.