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A study of phase transition, microstructure, and dielectric properties of Ba0.7Sr0.3Ti1–xNixO3 (BSTN) ceramics prepared by slow-injection solgel technique with x ranging from 0 to 1 mol% is reported in this article. The as-prepared BSTN material was calcined at 800 and 1000°C and subsequently sintered at 1100 and 1200°C, respectively. The optimized condition was found to be Ba0.7Sr0.3TiO3 doped with 1 mol% nickel calcined at 1000°C and sintered at 1200°C having the lowest dielectric loss of 0.02 with a dielectric constant of 1603 which was measured at a frequency of 1 kHz at room temperature.

Barium strontium titanate (BST) and iron doped barium strontium titanate (BSTF) ceramics with general formula (Ba0.5Sr0.5Ti1−yFeyO3) and different iron (Fe) contents were prepared by slow rate injection sol–gel technique. The phase analysis, morphology and dielectric properties of BSTFs were investigated. The phase analysis was carried out using XRD which revealed the crystallization of BSTF in perovskite structure with single phase. The Fe doped BST peaks shifted toward higher angles and the calculated crystallite size was 19 nm on average. The BSTF morphology was studied using TEM which showed that the particle size was affected by Fe content. The average particle size was found to be 37 nm for (Ba0.5Sr0.5Ti1−yFeyO3) with Fe concentration of (y = 0.01, 0.05 and 0.1) calcined at (600, 800 and 1000 °C). The dielectric measurements were carried out using impedance analyzer at room temperature as a function of frequency in the range of 10 Hz to 1 MHz. The dielectric constant and dielectric loss of the 1 mol% Fe-doped Ba0.5Sr0.5TiO3 at 1 kHz were 1453.69 and 0.0063, respectively. The BSTF ceramics with high dielectric constant and low dielectric loss were obtained for the application DRAM cell capacitor.

Varied compositions in the barium strontium titanate ternary system were prepared through the slow injection sol–gel technique. Nickel dopant was introduced through a general formula of Ba1 −xSrxTi1 −yNiyO3 (x = 0·4 and 0·5; y = 0·1 and 0·4 mol-%). Thermogravimetric analysis revealed that barium strontium titanate gels were completely dried and stabilised at 1000°C. All barium strontium titanate samples were confirmed as phase pure perovskite by qualitative X-ray diffraction analysis in which Nickel-doped subsolidus solution was formed successfully after calcinations at 1000°C. On the other hand, there was a sign of agglomeration discernible in the prepared BST samples and the grain sizes were found to be in the range of 39·66–71·87 nm.

Varied compositions in the barium strontium titanate ternary system were prepared through the slow injection sol–gel technique. Nickel dopant was introduced through a general formula of Ba1 −xSrxTi1 −yNiyO3 (x = 0·4 and 0·5; y = 0·1 and 0·4 mol-%). Thermogravimetric analysis revealed that barium strontium titanate gels were completely dried and stabilised at 1000°C. All barium strontium titanate samples were confirmed as phase pure perovskite by qualitative X-ray diffraction analysis in which Nickel-doped subsolidus solution was formed successfully after calcinations at 1000°C. On the other hand, there was a sign of agglomeration discernible in the prepared BST samples and the grain sizes were found to be in the range of 39·66–71·87 nm.

Ba0.6Sr0.4TiO3 was prepared through slow rate sol-gel route, characterized and investigated to determine the suitability as a dielectric material in the capacitor of a DRAM cell. X-ray diffractometer results show that single phase formation occurred at 800°C. The crystalline size of Ba0.6Sr0.4TiO3 was found to be in the range of 74.21 nm to 98.76 nm. Scanning electron microscopy analysis shows that the particles are spherical in nature and in the sample calcined at 800°C do not agglomerate. The dielectric constant range ranges from 408 to 1042 and the dielectric loss ranges (measured at 1 kHz) from 0.065 to 0.232.

Nickel-Iron (Ni-Fe) thin films were pulse-electrodeposited on copper (Cu) substrates under galvanostatic mode in the presence/absence of an ultrasonic field. The as-prepared thin films were characterized by X-Ray Diffractometer (XRD) and Scanning Electron Microscopy (SEM). The XRD results confirmed the deposition of NiFe on Cu substrates and the crystallite size calculated from Scherrerpsilas formula is 22.28 nm and 20.17 nm respectively for the films fabricated in the absence and presence of ultrasonic field. The grain sizes, from SEM micrographs, were found to be 225.52 nm and 79.64 nm respectively for the films fabricated in the absence and presence of ultrasonic field and the grains were in the shape of spherical balls.

Barium Strontium Titanate powder in the form of nano cubic particles has been prepared using slow rate gellification by sol-gel method. X-Ray Diffractometer results show that single phase formation occurred at 800 °C and the crystallite size for this sample was found to be 36.06 nm. Scanning Electron Microscopy analysis shows that the particles in the sample calcinated at 800 °C do not agglomerate and the average particle size was found to be 42.30 nm. The nano particle size analyzer results show a narrow particle distribution with good uniformity.