Y掺杂浓度梯度对BST薄膜结构及介电性能的影响  

Effect of Gradient of Y Doped Concentration on Structure and Dielectric Properties of BST Films

作　　者：张宝[1] 廖家轩[1] 王滨[1] 徐从玉[1] 

机构地区：[1]电子科技大学电子科学技术研究院,成都610054

出　　处：《人工晶体学报》2013年第3期487-490,共4页Journal of Synthetic Crystals

基　　金：国家自然科学基金(51172034);中央高校基本科研业务费专项资金(ZYGX2009X018);电子科技大学中青年学术带头人培养基金(Y02018023601053)

摘　　要：用改进的溶胶-凝胶(Sol-gel)法制备6层钇(Y)掺杂浓度分别为1%/1.1%/1.2%/1.3%/1.4%/1.5%的梯度Ba0.6Sr0.4TiO3薄膜(1-1.5YBST)和掺杂浓度分别为1%/1.3%/1.6%/1.9%/2.2%/2.5%的梯度Ba0.6Sr0.4TiO3薄膜(1-2.5YBST),研究掺杂浓度梯度对薄膜结构及介电性能的影响。X射线衍射(XRD)表明,两薄膜主要沿(110)晶面生长,为立方钙钛矿结构,比6层Y掺杂浓度均为1%的BST薄膜(YBST)的衍射峰强度及晶化减弱,但掺杂浓度梯度较大的1-2.5YBST对应的衍射强度和晶化较强。原子力显微镜(AFM)表明,1-2.5YBST具有更光滑的形貌。两薄膜比YBST具有高的电容、低的介电损耗、高的调谐率,而1-2.5YBST具有更优异的综合介电性能:零偏压下的电容为17.45 pF(介电常数127)、介电损耗为0.82%及最大调谐率为34.6%、优质因子为42。Six-Layer Yttrium（Y） grade doped Ba0.6Sr0.4TiO3 thin films （1-1.5YBST and 1-2.5YBST） with doping concentrations of 1%/1.1%/1.2%/1.3%/1.4%/1.5% and 1%/1.3%/1.6%/1.9%/2.2%/2. 5% have been prepared on Pt/Ti/SiO2/Si substrate by improved sol-gel method. The effect of the gradient of Y doping concentration on the structure and dielectric properties of two films has been researched. X-ray diffraction （XRD） showed that two films mainly grow along （110） orientation and show cubic perovskite structure. Compared to the six-layer 1% Y doped BST film, the diffraction peak intensity and crystallization weaken. However, 1-2. 5YBST with larger concentration gradient has stronger diffraction intensity and crystallization. Atomic force microscope（AFM） presented that 1-2.5YBST has smoother and denser morphology, smaller surface roughness and grain size. 1-1.5YBST and 1-2. 5YBST have larger capacitance （dielectric constant）, lower dielectric loss and higher tunability. 1-2. 5YBST shows better combination of dielectric properties with capacitance of 17.45 pF （ dielectric constant 127） and dielectric loss （tan） of 0.82% at zero bias, and tunability of 34.6% and figure of merit of 42 at 40 V.

关 键 词：掺杂浓度梯度 钛酸锶钡薄膜 溶胶-凝胶法 介电性能 

分 类 号：O484[理学—固体物理]