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Researchers are paying constant attention to preparing ceramic materials faster and cheaper while obtaining optimal physical properties. Their goal is to achieve a smaller grain size that will enable them to enhance the breakdown strength, thus increasing the density and efficiency of energy storage material. In line with this objective, two samples of Sr0.95Bi0.05TiO3 ceramics were selected: one was sintered at 1250 °C for 4 h using a conventional sintering CS process, while the other was sintered at the same temperature for 20 min using a microwave sintering system MWS. Both sintered samples showed a single cubic phase, as confirmed by refinement of the X-ray diffraction data. Morphological results show that the microwave-sintered sample ceramics show better densification exceeding 98%. The morphological results also show that the grain size obtained via microwave sintering is ten times smaller than that obtained with the conventional sintering technique. The P–E loop study shows that the breakdown strength with a microwave sintering system increased 1.5 times compared to the CS technique, resulting in enhanced energy storage density from 0.215 to 0.325 J/cm3. This intriguing technology has energy-saving qualities, quick processing, and homogeneous temperature distribution over the sample. According to our findings, the microwave processing method is one of the most attractive methods that can be used to develop new electronic materials for the next generation of applications. [ABSTRACT FROM AUTHOR]

We report an athermal laser annealing technique to fabricate a high-density array of gold nanoparticles on the surface of hafnium oxide thin films without altering the phase of HfO2. Au (~ 5 nm) films deposited on amorphous HfO2 (~ 10 nm) are subjected to laser annealing by using an Excimer laser (248 nm) to produce Au nanoparticles. It is important to note that the usual thermal methods would change the phase of the HfO2. It is observed that the size of the spherical Au nanoparticles decreases and their surface density increases as the number of laser pulses increases. These Au nanoparticles has induced a significant enhancement in the Raman signature of the standard R6G dye. Further, Metal–Oxide–Semiconductor capacitors were fabricated by depositing another layer of HfO2 followed by metal contacts on the surface of these nanoparticles. The leakage current conduction through the gate oxide with and without embedded nanoparticles has been studied using the Poole–Frenkel and Fowler–Nordheim tunneling mechanisms by examining the leakage current–voltage characteristics. PF tunneling is found to be prominent in these MOS structures with Au nanoparticles, which is attributed to the possible charge trapping by the embedded Au nanoparticles. The capacitance–voltage (C–V) characteristics show a significant broadening in the hysteresis loop indicating the improvement in the storage capacity of these MOS capacitors. [ABSTRACT FROM AUTHOR]

Barium strontium titanate Ba0.6Sr0.4TiO3 (BST6) thin films are deposited by pulsed laser deposition method at different laser fluences keeping the oxygen pressure constant. X-ray diffraction analysis confirms the formation of single phase cubic BST6 thin films. The strain in the grown films have been investigated, and the results show that the strain is in increased under the application of varying laser fluences. It can be inferred that the laser fluence is an important parameter in tuning the dielectric/ferroelectric properties of the films under optimized conditions. The thin films microstructures have been studied using HRTEM, and the results shows the presence of (110) faceted planes of BST6 with dspacing ~ 2.72-2.79 Å. The optical band gap of the BST6 thin films was calculated by applying the Tauc relation from the transmission spectra in the 190-2500 nm range. The BST6 thin films grown at 2 J cm−2 which shows the best microstructural and optical properties was selected for the microwave dielectric measurements by depositing a test circular patch capacitor. The microwave tunability and dielectric constant (εr) of a well crystallized BST6 thin film were found to be ~ 56 and ~ 284%, respectively at 1 GHz making it suitable for applications in tunable microwave devices. [ABSTRACT FROM AUTHOR]