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Te ions existed as Te[sub6+] in the Bi[sub6]Ti[sub5]TeO[sub22] (BIT) film grown at 300°C under a high oxygen pressure (OP) of 80.0 Pa and contributed to the formation of the crystalline BTT phase after subsequent annealing at 600°C. However, for the BTT film grown under a low OP of 53.3 Pa (or 9.33 Pa), Te[sub6+] ions, were converted to Te[sup4+] ions, which induced the phase transition of the BTT phase to the pseudo-Bi[sub4]Ti[sub3]O[sub12] and pseudo-Bi[sub2]Ti[sub2]O[sub7] phases after annealing at 600°C. The leakage current density decreased with increasing OP during the growth due to the decreased number of oxygen vacancies. The breakdown voltage also improved with increasing OP during the deposition. The Mn ions introduced in the BIT films by Mn doping existed as Mn[sup2+] or Mn[sup4+] and acted as the acceptors. This Mn doping to 10 mol % also reduced the leakage current density and increased the breakdown voltage by decreasing the number of intrinsic oxygen vacancies. [ABSTRACT FROM AUTHOR]

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]

Bi6Ti5TeO22 (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 BIT 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. [ABSTRACT FROM AUTHOR]