Structural and Electrical Properties of Bi5Nb3O15 Thin Films for MIM Capacitors with Low Processing Temperatures.

Bi₅Nb₃O₁₅ (B₅N₃) thin films were well formed on a Pt/Ti/SiO₂/Si substrate using radio-frequency magnetron sputtering. The crystalline B₅N₃ phase was developed for the films grown at temperatures above 450°C, but it decomposed into the BiNbO₃ phase when the growth temperature exceeded 550°C, probably due to the evaporation of Bi₂O₃. The dielectric constant (k) of the B₅N₃ film grown at room temperature was approximately 42 and increased with increasing growth temperature, reaching a maximum value of 160 for the film grown at 550°C. In particular, the B₅N₃ films grown in the temperature range of 200-300°C showed a high k value of 70 with a low dissipation factor (<1.0%), and their leakage current density was very low with a high breakdown voltage. Therefore, B₅N₃ films grown at low temperatures (≤300°C) can be a good candidate material for metal-insulator-metal (MIM) capacitors which require low processing temperatures. [ABSTRACT FROM AUTHOR]