(001)高度择优取向Ba_(0.6)Sr_(0.4)TiO_3/Pt异质结的结构及性能  

Structure and Physical Properties of(001) Highly Oriented Ba_(0.6)Sr_(0.4)TiO_3/Pt Heterostructure

作　　者：郭哲[1] 刘保亭[1] 王军[1] 李曼[1] 张金平[1] 娄建忠[2] 

机构地区：[1]河北大学物理科学与技术学院,保定071002 [2]河北大学电子信息工程学院,保定071002

出　　处：《人工晶体学报》2010年第6期1475-1478,1498,共5页Journal of Synthetic Crystals

基　　金：国家自然科学基金(No.60876055;11074063)资助项目;河北省自然科学基金(E2008000620)资助项目;河北省应用基础研究计划重点基础研究项目(10963525D);高等学校博士点基金(No.20091301110002);河北省教育厅科学研究计划(No.2007416);河北省科学技术厅科学技术研究与发展指导计划(No.07215154);河北大学博士基金(y2006091)资助项目

摘　　要：采用射频磁控溅射法结合高真空后退火处理,在MgO（001）单晶基片上制备了Pt薄膜。应用脉冲激光沉积法在Pt/MgO上进一步生长了Ba0.6Sr0.4TiO3（BST）薄膜。借助X射线衍射仪（XRD）、铁电测试仪、LCR表研究了BST/Pt/MgO的结构和性能。研究发现,700℃真空退火可以保证Pt薄膜在MgO基片上实现（001）高度择优生长,以（001）Pt薄膜为模板,可以进一步获得（001）高度择优取向具有铁电性能BST薄膜。在100 Hz测试频率下,BST薄膜最大介电常数为1100、调谐率为81%、品质因数为21;在7 V的电压下,漏电流密度1.85×10-5A/cm2,进一步分析表明,BST薄膜在0-2.6 V之间满足欧姆导电机制,在2.6-7 V之间满足普尔-弗兰克导电机制。Pt film was prepared on MgO（001） single crystal substrate using radio-frequency magnetron sputtering,combined with high vacuum post annealing process.BST film was further fabricated on Pt/MgO by pulsed laser deposition method.The structure and physical properties of BST/Pt/MgO heterostrucutre were characterized by XRD,ferroelectric tester,and LCR meter.The results showed that Pt film is highly（001） oriented after 700 ℃ vacuum annealing,and（001） highly oriented BST film with ferroelectric property can be obtained using（001） Pt as template.The test frequency is 100 Hz,the maximum dielectric constant,tunability and dielectric loss of a BST capacitor are 1100,81%,0.074,respectively.The leakage current density of the BST capcitor is 1.85×10-5 A/cm2 at 7 V.Schottky conduction mechanism is found to dominate the current conduction at low voltages ranging from 0 to 2.6 V,and at the voltages,ranging from 2.6-7 V,BST capacitor meets Poole-Frenkel emission conduction.

关 键 词：BST薄膜 脉冲激光沉积 导电机制 

分 类 号：O484.4[理学—固体物理]