Humidity Sensing Properties of Ferroelectric Compound Ba0.7Sr0.3TiO3 Thin Films Grown by Pulsed Laser Deposition

BaSrTiO3(BST) is a solid solution prepared by Sol-Gel method. A ternary compound of BST is composed of from solid solution BaTiO3 and SrTiO3. BST thin films prepared by PLD method and their humidity sensing characteristics have been investigated. The films were formed on Si substrates with Au electrodes. XRD pattern showed tetragonal phase and no significant change between film and bulk. SEM revealed a uniform distribution of cubic particles shape and nanoparticles size. Capacitive and Resistive humidity sensors were made based on BST/Si thin film used co- planer form and the corresponding sensing properties were investigated. Experimental results showed on that the sensor exhibited high sensitivity and good stability. The humidity relative increased then the capacitive increased and resistivity decreased