Dielectric properties of random and 〈100〉 oriented SrTiO3 and (Ba,Sr)TiO3 thin films fabricated on 〈100〉 nickel tapes

Abstract

Properties are presented for random and enhanced 〈100〉 orientation ${\mathrm{SrTiO}}_3$ and ${\mathrm{Ba}}_x{\mathrm{Sr}}_{\text{1−x}}{\mathrm{TiO}}_3$ $\text{(x=0.33,}$ 0.50, and 0.67) films fabricated on base-metal 〈100〉 Ni tapes using a chemical solution deposition approach. Films were crystallized in a reducing atmosphere, which prevented Ni oxidation, but permitted growth of ${\mathrm{SrTiO}}_3$ and ${\mathrm{Ba}}_x{\mathrm{Sr}}_{\text{1−x}}{\mathrm{TiO}}_3$ films with dielectric loss $\tan \mathrm{ \delta }$ between 0.003 and 0.015. For randomly oriented ${\mathrm{Ba}}_x{\mathrm{Sr}}_{\text{1−x}}{\mathrm{TiO}}_3$ $\text{(x=0,}$ 0.33, 0.5, and 0.67) films, zero-field 100 kHz dielectric constants ranged from 250 to 420. Films with enhanced 〈100〉 orientation exhibited zero-field dielectric constants of 980 to 1500, three times higher than random films. Development of such high dielectric constants on Ni suggests a future method for inexpensive, high performance base-metal electrode capacitor fabrication.