Fabrication of Barium Strontium Titanate Films Directly on Copper Electrodes by Aerosol Deposition Method for Multilayer Dielectric Devices

摘要

We demonstrate a preparation of polycrystalline barium strontium titanate (Ba{sub}xSr{sub}(1-x)TiO{sub}3, BST) films directly on base metal copper electrodes using aerosol deposition method (ADM) at room-temperature and explore metal Cu thin films on glass substrate. The dielectric constant of the as-deposited Ba{sub}xSr{sub}(1-x)TiO{sub}3 film were 100, 201, and 72 at x = 1.0, 0.6, 0.4, respectively. After annealing in N{sub}2 gas ambient at 500°C, the dielectric constant of the film on the Cu electrode were 190, 400, and 170 at x = 1.0, 0.6, 0.4, respectively. At the BST(x=0.6) film annealed at more than 400°C, a high tunability of 30% can be obtained at an applied electric field of 150 kV cm{sup}(-1). Moreover, as-deposited BST (x=0.6) film even showed a tunability of 15%. The Cu films deposited by AD method on the glass substrate showed a volume resistivity of 1.3×10{sup}(-4)Ωcm at as-deposited state and 4.5×10{sup}(-6)Ωcm after vacuum annealing at 300°C, respectively.