Effect of cerium doped concentration on grain growing modes of BST powder

ABSTRACT Cerium (Ce) doped barium strontium titanate (Ce-BST) powder was prepared by sol-gel method, and the effect of Ce doped concentration on growing modes of grains of the Ce-BST powder was studied. X-ray diffraction (XRD) reveals that all Ce-BST powders show cubic perovskite structures. It can be found that increasing Ce doped concentration corresponds to decreasing lattice parameter until the doped concentration increases to 3% mol ratio, and then the continuingly increasing doped concentration corresponds to increasing lattice parameter. Scanning electron microscopy (SEM) exhibits that all powders are composed of nano-grains, but the growing modes of the grains strongly depend on the doped concentration. When doped concentration is not more than 1% mol ratio, the grains show globular growth; when the doped concentration is not less than 3% mol ratio, the grains show layered growth; when the doped concentration ranges from 1% mol ratio to 3% mol ratio, columnar grains appear in the globular powders. Also, the dielectric properties of the powders are presented and the related mechanisms are discussed.

[1]  D. Cros,et al.  Tunable RF-Filter Using Mn-Doped BST Ceramic Varactors , 2010 .

[2]  Qing Xu,et al.  Effect of sintering temperature on structure and nonlinear dielectric properties of Ba0.6Sr0.4TiO3 ceramics prepared by the citrate method , 2010 .

[3]  Qing Xu,et al.  Low-temperature synthesis of superfine barium strontium titanate powder by the citrate method , 2010 .

[4]  Haitao Huang,et al.  Structural and electric properties of barium strontium titanate based ceramic composite as a humidity sensor , 2008 .

[5]  Ho-Gi Kim,et al.  Annealing effect on dielectric and leakage current characteristics of Mn-doped Ba0.6Sr0.4TiO3 thin films as gate insulators for low voltage ZnO thin film transistor , 2008 .

[6]  D. C. Agrawal,et al.  Effect of uniform and periodic doping by Ce on the properties of barium strontium titanate thin films , 2007 .

[7]  Chang-I. Kim,et al.  Electrical and dielectric properties of Ce-doped Ba0.6Sr0.4TiO3 thin films , 2006 .

[8]  H. B. Lu,et al.  Ce-doping effects on electronic structures of Ba0.5Sr0.5TiO3 thin film , 2006 .

[9]  H. Tuller,et al.  Mn-doped Ba0.6Sr0.4TiO3 high-K gate dielectrics for low voltage organic transistor on polymer substrate , 2005 .

[10]  P. Vilarinho,et al.  Structure–microstructure–dielectric tunability relationship in Mn-doped strontium titanate ceramics , 2005 .

[11]  H. B. Lu,et al.  Influence of Ce doping on leakage current in Ba0.5Sr0.5TiO3 films , 2005 .

[12]  Weidong Si,et al.  Near single crystal-level dielectric loss and nonlinearity in pulsed laser deposited SrTiO3 thin films , 1998 .

[13]  H. Jantunen,et al.  Tunable microwave devices using low-sintering-temperature screen-printed barium strontium titanate (BST) thick films , 2010 .