铬掺杂钛酸锶钡陶瓷的介电调谐性能  

Dielectric tunable properties of Cr-doped barium strontium titanate ceramics

作　　者：李儒兴[1] 龚佳[1] 程晋荣[1] 孟中岩[1] 

机构地区：[1]上海大学材料科学与工程学院,上海200072

出　　处：《材料研究学报》2007年第2期189-193,共5页Chinese Journal of Materials Research

基　　金：国家自然科学基金(50332030);上海市教委启明星计划(04qmx1440);上海市教委材料学重点学科资助项目

摘　　要：研究了Cr掺杂对钛酸锶钡(Ba0．6Sr0.4TiO3,BST)陶瓷的介电及其可调性能的影响．结果表明,少量的Cr可进入BST品格形成固溶体,并促进晶粒生长．当Cr掺杂量(摩尔分数)低于1．0％时,陶瓷的介电损耗急剧降低,调谐率明显提高,综合性能显著改善,其中Cr掺杂0．6％的BST陶瓷具有最佳的综合性能,其在1MHz下的介电损耗为0．0005,品质因子(FoM)达到500,而未掺杂样品的FoM值仅为60．Cr掺杂陶瓷损耗的急剧降低可归因于Cr3+离子的还原和Cr3+、Cr2+受主行为中和了氧空位的施主行为．The dielectric response and tunable properties of Cr-doped Ba0.6Sr0.4Ti03 ceramics were investigated. The samples were characterized by XRD and SEM, which reveal that the dopants have entered the unit-cell of the BST solid solution, and behave as grain-growth helper at lower doping level. Both of dielectric dissipation factor and tunability were obviously improved by doping with Cr concentration （mol fraction） lower than 1.0%, and hence the figure of merit （FoM） were effectively modified. The 0.6% Cr-doped specimen reveals optimized dielectric and tunable properties, with extremely low dissipation factor of 0.0005, and much higher FoM of 518.5, compared to the undoped specimen. The dramatic drop of the dissipation factor can be attributed to the reducing of Cr^3＋ to Cr^2＋ and the neutralization of the donor action of oxygen vacancies by acceptor action of Cr^3＋ and Cr^2＋.

关 键 词：无机非金属材料 钛酸锶钡 CR掺杂 调谐率 介电损耗 

分 类 号：TN304[电子电信—物理电子学]