INVESTIGATION OF THE EFFECT OF PARTICLE-SIZE ON THE OPTICAL AND ELECTRONIC-PROPERTIES OF BA1-XSRXTIO3 COMPOSITE CERAMICS

As a part of an effort to optimize the performance of the ceramic phas e shifters, various composites of barium strontium titanium oxide (Ba1 -xSrxTiO3; BSTO; 0 less than or equal to x less than or equal to 1) co mbined with other nonelectrically active oxide ceramics have been form ulated which possess low loss tangents and have high tunabilities. To further engineer the electronic properties of the materials, we have s tudied the effect of ball-milling on the powder characteristics of Ba0 .6ST0.4TiO3/MgO[1] composite ceramics. The effect of the reduction of the overall particle size of the materials from ball-milling is depend ent on the additive oxide content; for samples with oxide content > 5. 0 wt%, the dielectric constant, and tunability (%) are decreased. Addi tionally, the materials have been characterized using FTIR, FT-Raman s pectroscopy, x-ray diffraction, and grain size analysis has been perfo rmed.