YBa_2Cu_3O_(7-δ)/Ba_(0.05)Sr_(0.95)TiO_3双层膜的制备及微波频率下的介电性能研究  

PREPARATION AND DIELECTIC PROPERTIES IN MICROWAVE FREQUENCY OF YBa_2Cu_3O_(7-δ)/Ba_(0.05)Sr_(0.95)TiO_3 DOUBLE LAYER FILMS

作　　者：李娜[1] 夏丰金[1] 王旭[1] 徐云辉[1] 白丹丹[1] 孙亮[1] 何豫生[1] 

机构地区：[1]中国科学院物理研究所,北京100190

出　　处：《低温物理学报》2013年第4期255-259,共5页Low Temperature Physical Letters

摘　　要：利用脉冲激光沉积(PLD)技术,在MgO衬底上外延生长YBa2Cu3O7-δ/Ba0.05Sr0.95TiO3薄膜.使用光刻和离子束刻蚀技术,将顶电极制作成插指状,构成BST平面插指电容,研究Ba0.05Sr0.95TiO3薄膜在微波频率下的电调谐性能.测试结果表明:在76K,外加直流偏压从0V变到160V,Ba0.05Sr0.95TiO3薄膜的相对介电常数从1160降低到252(可调率约为78%),变容器的损耗角从0.02降到0.009.该YBa2Cu3O7-δ/Ba0.05Sr0.95TiO3异质结薄膜介电可调率高,损耗正切小,与国际最好水平相当.YBa2Cu3O7-δ/Ba0.05Sr0.95TiO3 double layer thin films were grown by pulsed laser deposition on single crystal MgO （001） substrate. The interdigital varactors were fabricated by standard photolithographic process and ion-beam etching technique to investigate the dielectric properties of the Ba0.05Sr0.95TiO3 thin film in microwave fre- quency. With the application of 160V tuning voltage at 76K, dielectric constant of the Ba0.05Sr0.95TiO3 thin film decreased from 1160 to 252 （-78% tuning） and the loss tangent of the varactor varied from 0. 02 to 0. 009. The YBa2Cu3O7-δ/Ba0.05Sr0.95TiO3 heterostructure thin film has the same level of tunability andloss tangent with the best results in the literature reported.

关 键 词：BA0 05Sr0 95TiO3薄膜 YBa2Cu3O7-δ薄膜 可调率 损耗角正切 

分 类 号：O484.1[理学—固体物理]