Investigation on Tunable Performance of BMN/BST Multilayer and BMN–BST Composite Thin Films

Abstract

The BMN/BST multilayer and BMN-BST composite thin films have been fabricated by pulsed laser deposition on Au/ TiO x /SiO 2 /Si substrate. The multilayer thin films comprising one, two, and four periodic compositional Bi 1.5 MgNb 1.5 O 7 / Ba 0.6 Sr 0.4 TiO 3 (BMN/BST) layers (PCBLs) have been elaborated with the final same thickness. The four PCBLs show the largest dielectric constant of~168 and tunability of 40.6% at a maximum applied bias field of 0.67 MV/cm and the lowest loss tangent of~0.006, whereas the figure of merit (FOM) is 72. The BMN-BST composite thin films exhibit medium dielectric constant of~238, low loss tangent of~0.0053, and superior tunable dielectric properties at room temperature. Calculations of tunability and FOM display a maximum value of 49.3% at 670 kV/cm and~88, respectively.

Effect of oxygen pressure on preferential orientation, microstructure and functional properties of Bi1.5MgNb1.5O7 thin films prepared by pulsed laser deposition

“…3, the thin films deposited at oxygen pressure of 10 Pa demonstrated well crystallized cubic pyrochlore structure with minimum degree of preferred orientation, which is favorable to enhanced dielectric constant. According to Johnson's study [35] and our previous study [36], the higher the value of dielectric constant at zero electric field, the larger the dielectric tunability would be. As shown in Fig.…”

Ultra-high resistive switching current ratio and improved ferroelectricity and dielectric tunability performance in a BaTiO3/La0.7Sr0.3MnO3heterostructure by inserting a SrCoO2.5layer

“…These results show high dielectric tunability in both BTO and BTO/SCO, which are very competitive with the currently studied tunable ferroelectrics. 8,43–45 The tunability of the BTO films was enhanced by 8.6%, which was attributed to the introduction of SCO intercalation. BTO in the bilayer has greater out-of-plane strain, which is beneficial for inducing higher tunability in the films.…”

Effect of internal interface layer on dielectric properties of doped Ba0.6Sr0.4TiO3 thin films and its simulation in filters

“…In addition, when the size of the ferroelectric phase shifter and tunable filter is reduced to the nanometer level, the size effect of the ferroelectric thin film inevitably affects the performance of the device. Therefore, in view of the above problems, researchers have carried out many studies, such as introducing acceptor impurities and creating multilayer gradient structures [16][17][18][19][20]. Cole studied the influence of the acceptor doping ion (Mg 2+ ) on the dielectric properties of BST films [17].…”