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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]