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Bismuth zinc niobate (BZN) thin films with excess Zn contents were deposited from the ceramic targets containing various excess amounts of ZnO (0–20 mol%) on Pt/TiO 2 /SiO 2 /Si substrate by RF magnetron sputtering at room temperature. As-deposited thin films were post-annealed at a temperature ≤200 °C, which is compatible with PCB substrates. The effect of Zn deficiency and Zn excess on the microstructure, dielectric, and electrical properties of BZN thin films was studied. As-deposited and post-annealed BZN thin films at a temperature ≤200 °C were amorphous in nature. An appropriate amount of excess zinc improves the dielectric and electrical properties of BZN thin films, while too much excess zinc leads to deteriorate the properties. BZN thin film with 5 mol% excess Zn content exhibits the maximum dielectric constant of 64 with a very low loss of 0.6%, measured at 10 kHz and the leakage current of less than 1 µA at an applied electric field of 200 kV/cm. [ABSTRACT FROM AUTHOR]

Bi 1.5 Zn 1.0 Nb 1.5 O 7 (BZN) thin films with thickness from 60 nm to 200 nm were prepared by radio-frequency magnetron sputtering and post-annealed from 550 °C to 650 °C. The x-ray diffraction results indicated that the BZN thin films possessed a cubic pyrochlore phase. The BZN thin films exhibited thickness-independent dielectric properties with dielectric constant of ~180 and low loss tangent less than 1% at 10 kHz as the film thickness decreased to 60 nm. The BZN thin films with thickness of 200 nm and post-annealed at 650 °C had a tunability of 32.7% at a DC bias field of 1.5 MV/cm. The results suggest that the BZN thin films have promising applications on the embedded capacitors, tunable devices and energy storage devices. [ABSTRACT FROM AUTHOR]

Abstract: Bi2Zn2/3Nb4/3O7 thin films were deposited on Pt/TiO2/SiO2/Si(100) substrates at a room temperature under the oxygen pressure of 1–10Pa by pulsed laser deposition. Bi2Zn2/3Nb4/3O7 thin films were then post-annealed below 200°C in a rapid thermal process furnace in air for 20min. The dielectric and leakage current properties of Bi2Zn2/3Nb4/3O7 thin films are strongly influenced by the oxygen pressure during deposition and the post-annealing temperature. Bi2Zn2/3Nb4/3O7 thin films deposited under 1Pa oxygen pressure and then post-annealed at a temperature of 150°C show uniform surface morphologies. Dielectric constant and loss tangent are 57 and 0.005 at 10kHz, respectively. The high resolution TEM image and the electron diffraction pattern show that nano crystallites exist in the amorphous thin film, which may be the origin of high dielectric constant in the Bi2Zn2/3Nb4/3O7 thin films deposited at low temperatures. Moreover, Bi2Zn2/3Nb4/3O7 thin film exhibits the excellent leakage current characteristics with a high breakdown strength and the leakage current density is approximately 1×10−7 A/cm2 at an applied bias field of 300kV/cm. Bi2Zn2/3Nb4/3O7 thin films are potential materials for embedded capacitor applications. [Copyright &y& Elsevier]

Abstract: Bi2Zn2/3Nb4/3O7 thin films were deposited at room temperature on Pt/Ti/SiO2/Si(100) and polymer-based copper clad laminate (CCL) substrates by pulsed laser deposition. Bi2Zn2/3Nb4/3O7 thin films were deposited in situ with no intentional heating under an oxygen pressure of 4Pa and then post-annealed at 150°C for 20min. It was found that the films are still amorphous in nature, which was confirmed by the XRD analysis. It has been shown that the surface roughness of the substrates has a significant influence on the electrical properties of the dielectric films, especially on the leakage current. Bi2Zn2/3Nb4/3O7 thin films deposited on Pt/Ti/SiO2/Si(100) substrates exhibit superior dielectric characteristics. The dielectric constant and loss tangent are 59.8 and 0.008 at 10kHz, respectively. Leakage current density is 2.5×10−7 A/cm2 at an applied electric field of 400kV/cm. Bi2Zn2/3Nb4/3O7 thin films deposited on CCL substrates exhibit the dielectric constant of 60 and loss tangent of 0.018, respectively. Leakage current density is less than 1×10−6 A/cm2 at 200kV/cm. [Copyright &y& Elsevier]