Ultrasonic mist chemical vapor deposition and dielectric properties of cubic pyrochlore bismuth magnesium niobate thin films

Abstract

Ultrasonic mist chemical vapor deposition (mist-CVD) process has been used to deposit bismuth-based cubic pyrochlore thin films for the first time. The crystal structure, morphology, and dielectric properties of Bi1.5MgNb1.5O7 (BMN) films grown in N2, air, and O2 carrier gas are characterized. Sufficient O2 is beneficial for the pure phase and highly crystallized cubic pyrochlore BMN thin films with a (2 2 2)-preferred orientation. Superior dielectric properties (dielectric constant 176, loss tangent 0.005, and tunability 29%@ ∼1 MV cm−1) at 1 MHz are obtained. The results suggest that the mist-CVD method have potential in depositing high quality bismuth-based cubic pyrochlore thin films.

Ultrahigh-Energy Storage Properties of (PbCa)ZrO3 Antiferroelectric Thin Films via Constructing a Pyrochlore Nanocrystalline Structure

“…It must be noted, however, that the dielectric constant and dielectric loss of the films with the nanocrystalline structure of pyrochlore phase did not change with frequency, which indicates that the pyrochlore materials have excellent dielectric properties, such as medium dielectric constant and low dielectric loss, and may have high breakdown strength. 31,32 Similarly, the temperature dependence of the dielectric constant and loss of these films was also closely related to the crystalline phase and phase composition of the films (Figure S5). As a result, the dielectric properties of the PCZ films can be controlled by microstructure.…”

High energy storage of PbZrO3 antiferroelectric thin films via constructing phase composition

“…However, the tanδ for films annealed at 550 °C, 600 °C and 620 °C shown low values. Moreover, as can be seen from figures 4(a) and (b), the ε r and tanδ of the film containing the pyrochlore phase almost never change with frequency, indicating that the material has excellent dielectric properties and may show higher breakdown strength [40,41]. Additionally, the values of dielectric loss and dielectric constant at different annealing temperatures measured at 1 kHz are included in table 1. pyrochlore phase which weakens the ordering of ferroelectric polarization in the perovskite phase, leading to a decrease of the maximum polarization.…”