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Barium strontium titanate (BST) was produced in a teflon lined pressure vessel using a high temperature hydrothermal technique and controlling the processing parameters of Ba+Sr concentration, Ba and Sr ratio, temperature, reaction period and TiO₂ concentration. It was found that this technique produces BST powders of less than 200 nm particle size with high degree of crystallinity. However, most BST powders tend to be strontium rich. Thus, excess barium in the initial solution was essential in order to produce a high barium content in the final product, which was important to obtain good electrical properties. A high TiO₂ concentration was also crucial in producing BST with a high Ba content, though this parameter was responsible for a multiphase structure. The period of hydrothermal reaction was important for stoichiometric reaction.

This effort aimed to investigate the differences between raw materials and thin films to enhance the film performance and get encouraging results. Barium strontium titanate (BST) is a solid solution consisting of titanate barium (BT) and titanate strontium (ST). BST powder was synthesized using the sol–gel process, and BST film was deposited using pulsed laser deposition (PLD). Barium, strontium acetate, and Ti-isopropoxide were utilized as raw material sources. XRD was used to characterize the BST perovskite crystal structure. The SEM and LCR meters revealed morphology surface and dielectric properties. XRD pattern shows a cubic structure phase. The particle size of the bulk exhibited 122.88nm while the film particle size was 84nm. The dielectric constant of the bulk shape exhibited was greater than the form of the films, which was attributed to different thicknesses, densities, defects, and porosity.

(Pb,La)TiO₃ (PLT) and Pb(Zr,Ti)O₃ (PZT) thin films were deposited on Pt/SiO₂/Si substrate by metal-organic chemical vapor deposition (MOCVD) using a solid delivery system. The domain configurations of the deposited PLT thin films were investigated, and the film with a columnar structure exhibited a very stable write/read operation for the domain memory application. Electrical properties of PLT, PZT and rf-sputter-deposited (Ba,Sr)TiO₃ (BST) thin films were measured, and their conduction mechanisms were analyzed. The composition and thickness uniformity of BST thin films deposited by the low temperature MOCVD method on a patterned wafer with 0.15 μm-diameter contact holes were investigated, and complete thickness and composition uniformity were obtained especially for the case of a dome-wall-type chamber with a wall temperature of 450°C.

The dielectric properties of Ba_0.6Sr_0.4TiO₃ (BST) thin films deposited using SrRuO₃ (SRO) materials as bottom electrode were compared with those of the films grown using La_0.5Sr_0.5CoO₃ (LSCO) materials as bottom electrode. X-ray diffraction scanning revealed that the two kinds of films could be epitaxially grown in pure single-oriented perovskite phases and atomic force microscopy showed that the root mean square roughness of BST/SRO films were similar to BST/LSCO films. The dielectric properties of the BST/SRO and BST/LSCO thin films were measured at 10 kHz and 300 K with a parallel-plate capacitor configuration. Compared with BST/LSCO, the dielectric tunability for BST/SRO films slightly decreased, while the loss decreased synchronously. The figure of merit factor value increases from 25.67 for BST/LSCO films to 48.76 for BST/SRO films under an applied voltage of 6 V. The leakage current density of the thin films at a positive voltage of 2 V decreases from 2.41 × 10^-7A/cm² for BST/LSCO to 8.41 × 10^-8A/cm² for BST/SRO. This phenomenon is ascribed to the smaller strain induced in BST/SRO materials.

Single layered Ba_0.6Sr_0.4TiO₃ (BST) thin films were prepared on stainless steel (304) and quartz substrates by solution method. The microstructure, grain size, surface morphology and thickness of the films were reported on the basis of X-ray diffraction (XRD), atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM) and UV-visible spectrometer. Variation in thickness influences the microstructure of the films. The single layered thin film had uniform crack-free surface morphology. The low frequency dielectric constants for the films of thicknesses 663, 476 and 451 nm were found to be 1246, 859 and 703, respectively at room temperature. The dielectric loss values for different thicknesses were found to be 0.238%, 0.170% and 0.120% for 100 kHz and 0.043%, 0.029 % and 0.028% for 1 kHz. The dielectric properties changed significantly with thickness of the film as well as with frequency. The tunability of the single layered BST film increased with film thickness. The refractive index, bandgap and thickness of the single layered thin film were calculated by using envelope method and Tauc's relation from the UV-visible transmission spectrum. The bandgap increases with the film thickness. These results show that this single layered film will be a potential material for tunable devices application.

Many biological systems are genuinely hybrids consisting of interacting discrete and continuous components and processes that often operate at different time scales. It is therefore desirable to create modeling frameworks capable of combining differently structured processes and permitting their analysis over multiple time horizons. During the past 40 years, Biochemical Systems Theory (BST) has been a very successful approach to elucidating metabolic, gene regulatory, and signaling systems. However, its foundation in ordinary differential equations has precluded BST from directly addressing problems containing switches, delays, and stochastic effects. In this study, we extend BST to hybrid modeling within the framework of Hybrid Functional Petri Nets (HFPN). First, we show how the canonical GMA and S-system models in BST can be directly implemented in a standard Petri Net framework. In a second step we demonstrate how to account for different types of time delays as well as for discrete, stochastic, and switching effects. Using representative test cases, we validate the hybrid modeling approach through comparative analyses and simulations with other approaches and highlight the feasibility, quality, and efficiency of the hybrid method.

Solid solutions of the composition Ba${{}_{1-}{}_x{}_{-}}_y$(Mg, Ln)${}_x$${\text{Sr}}_y$TiO₃ ($x$ = 0.01; 0.025; 0.04; $y$ = 0.20; 0.50; 0.80; Ln = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tu, Yb) were prepared by two-stage solid-phase synthesis followed by sintering using conventional ceramic technology. The influence of rare-earth elements on the microstructure of the prepared ceramic samples was investigated. It was found that regardless of the type of modifiers introduced, the grain landscape of the studied solid solutions with different amounts of SrTiO₃ is refined (in the initial system, the average grain size, $\bar{d}$, at $x$ = 0.20 is 6 $\mu$m; at $x$ = 0.50 is 4 $\mu$m; at $x$ = 0.80 is 18 $\mu$m) to crystallite sizes not exceeding (2-3) $\mu$m, and compacted. The using of mechanical activation procedures leads to an even greater decrease in the size and an increase in the density of ceramics. The increasing in the concentration of modifiers in each group (within the considered range of dopant variation) against the background of such a fine-grained structure has little effect on the dynamics of changes in $\bar{d}$. It is concluded that it is advisable to use the data obtained in the development of functional materials based on BST/(Mg, Ln) and devices with the participation of these compositions.