Deposition profile of rf-magnetron-sputtered Ba TiO ₃ thin films

BaTiO₃ thin films were fabricated using an rf-magnetron sputtering technique and an oxide target. In spite of depositing on an amorphous fused quartz substrate, the preferentially oriented thin films were obtained without any post-annealing process. The preferred orientation of the thin films changed with sputtering gas pressure, gas composition and substrate temperature. At a lower gas pressure, the thin films crystallized well and preferentially oriented to the [100] direction. With increasing gas pressure, the preferred orientation changed to (110). On the other hand, at a lower substrate temperature or higher argon partial pressure, the preferred orientation changed to (111). The variation of the preferred orientation, lattice constant, and crystallite size with sputtering conditions was explained by assuming a thermal-vibration model.