Structure and dielectric properties of (Sr_1-1.5x Bi_x) TiO₃ thin films

Bismuth doped SrTiO₃ material has shown very interesting phenomena. Dielectric and ferroelectric relaxations have been recently reported in bismuth doped SrTiO₃ ceramics in the lower temperature range. Thin films of bismuth doped SrTiO₃ [(Sr_1-1.5x Bi_x) TiO₃] (x=0.0,0.05,0.10) have been prepared by a sol-gel method and investigated in this work. The phases and surface morphologies of thin films were analyzed to assess the structures and crystallization. The structure of the thin films is revealed as a cubic perovskite structure with no other phase detected. The dielectric properties and dielectric tunability of (Sr _1-1.5x Bi_x) TiO₃ thin films have been studied as a function of doping amount of bismuth and discussed in detail.