Structural and electrical properties of Bi₆Ti ₅TeO₂₂ thin films grown on Pt/Ti/SiO₂/Si substrate

Bi6 Ti5 TeO22 (BTT) thin films were well formed on a Pt/Ti/ SiO2 /Si substrate using radio frequency magnetron sputtering. The dielectric constant (k) of the BTT films grown at room temperature was relatively high, approximately 54, and increased with increasing growth temperature to reach a maximum value of 107 for the film grown at 500°C. In particular, the 120 nm thick BTT films grown at 200-300°C showed high k -values of 63-69 with a low dissipation factor (<1.3%) due to the presence of the small BTT crystals (∼5 nm). The leakage current density of this film was very low, approximately 2× 10-10 A/ cm2, at 3 V. Therefore, the BTT film grown at low temperatures (300°C) is a promising candidate material for metal-insulator-metal capacitors which require low processing temperatures.