Dielectric and piezoelectric properties of highly (100)-oriented BaTiO3 thin film grown on a Pt/TiOx/SiO2/Si substrate using LaNiO3 as a buffer layer
Dielectric and piezoelectric properties of highly (100)-oriented BaTiO3 thin film grown on a Pt/TiOx/SiO2/Si substrate using LaNiO3 as a buffer layer
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DOI：
10.1016/j.jcrysgro.2005.07.017
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发表时间：
2005-10-15
影响因子：
1.8
通讯作者：
Kato, K
中科院分区：
文献类型：
--
作者：
Guo, YP;Suzuki, K;Kato, K
采用化学溶液沉积法，以LaNiO_3为缓冲层，在Pt/TiO_x/SiO_2/Si衬底上制备了BaTiO_3薄膜。研究了前驱液浓度和LaNiO_3缓冲层浓度对BaTiO_3薄膜的结晶度、取向度和取向程度的影响。在0.2mol/L浓度下，X射线衍射分析表明BaTiO_3薄膜具有高度的(100)择优取向。以LaNiO_3为缓冲层，可显著提高BaTiO_3的结晶质量。原子力显微镜观察到表面光滑，颗粒分布均匀，尺寸约为80 nm。研究了一步化学溶液沉积法制备的(100)取向薄膜的电学性能。薄膜厚度约为140 nm，介电常数约为340，介电损耗约为2.9%。BaTiO_3薄膜在外场作用下表现出良好的绝缘性。LaNiO_3缓冲层的引入将降低BaTiO_3薄膜的大电流发射起始时间。用原子力显微镜测得裸膜的压电系数为30 pm/V，是无规取向BaTiO_3薄膜的两倍。这些结果表明，高度(100)取向的BaTiO_3有望成为无铅薄膜压电材料的候选材料。(C)2005 Elsevier B.V.保留所有权利。
BaTiO3 thin films were deposited onto a Pt/TiOx/SiO2/Si substrate via the chemical solution deposition method, with LaNiO3 as a buffer layer. Effects of the concentration of precursor solution and LaNiO3 buffer layer on crystallinity and orientation, degree of BaTiO3 thin films have been investigated. At 0.2mol/l concentration, X-ray diffraction analyses show that the BaTiO3 films are highly (10 0)-oriented. The crystalline quality of BaTiO3 is significantly improved with LaNiO3 as a buffer layer. Smooth surface with evenly distributed grains as small as about 80 nm were observed by atomic force microscope. The electrical properties of the (10 0)-oriented films prepared by the one-step chemical solution deposition process have been studied. BaTiO3 thin films with a thickness of about 140 nm show a dielectric constant of similar to 340 and a loss tangent of similar to 2.9%. The BaTiO3 films show a good insulative characteristic against the applied field. The introduction of LaNiO3 buffer layer will decrease the onset of the high current emission of BaTiO3 films. A piezoelectric coefficient of 30 pm/V has been detected by the atomic force microscope on the bare film, which is twice as large as that of BaTiO3 thin film with random orientation. These results indicate that the highly (10 0)-oriented BaTiO3 should be a promising candidate as the lead-free thin film piezoelectrics. (c) 2005 Elsevier B.V. All rights reserved.