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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.

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.

To compensate for bismuth loss that occurred during the film deposition process, Bi 1.5 Zn 1.0 Nb 1.5 O 7 (BZN) thin films were deposited at room temperature from the ceramic targets containing various excess amounts of bismuth (0–20 mol%) on Pt/TiO 2 /SiO 2 /Si substrates by using RF magnetron sputtering technique. The effect of bismuth excess content on the microstructure and electrical properties of BZN thin films was studied. The microstructure and chemical states of the thin films were studied by SEM and XPS. EPMA was employed to assess the film stoichiometry. The X-ray diffraction analysis reveals that the BZN thin films exhibit the amorphous structure in nature. An appropriate amount of excess bismuth improves the dielectric and electrical properties of BZN thin films, while too much excess bismuth leads to deterioration of the properties. BZN thin film with 5 mol% excess bismuth exhibits a dielectric constant of 61 with a loss of 0.4% at 10 kHz and leakage current of 7.26×10 −7 A/cm 2 at an electric field of 200 kV/cm.

Bi 2 Zn 2/3 Nb 4/3 O 7 thin films were deposited at room temperature on Pt/Ti/SiO 2 /Si(1 0 0) and polymer-based copper clad laminate (CCL) substrates by pulsed laser deposition. Bi 2 Zn 2/3 Nb 4/3 O 7 thin films were deposited in situ with no intentional heating under an oxygen pressure of 4 Pa and then post-annealed at 150 °C for 20 min. 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. Bi 2 Zn 2/3 Nb 4/3 O 7 thin films deposited on Pt/Ti/SiO 2 /Si(1 0 0) substrates exhibit superior dielectric characteristics. The dielectric constant and loss tangent are 59.8 and 0.008 at 10 kHz, respectively. Leakage current density is 2.5 × 10 −7 A/cm 2 at an applied electric field of 400 kV/cm. Bi 2 Zn 2/3 Nb 4/3 O 7 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/cm 2 at 200 kV/cm.