YBCO沟槽型台阶结和rf SQUID的制备及性能研究  

PREPARATION AND PERFORMANCE RESEARCH OF YBCO STEP GRAIN BOUNDARY JUNCTIONS AND rf SQUIDs

作　　者：马平[1] 谢飞翔[1] 王守证[1] 刘乐园[1] 张凡 聂瑞娟[1] 胡晓东[1] 戴远东[1] 王世光 甘子钊[1] 

机构地区：[1]北京大学物理学系

出　　处：《低温物理学报》1999年第1期5-11,共7页Low Temperature Physical Letters

摘　　要：本工作在沟槽型台阶衬底上用直流磁控溅射法外延生长ＹＢａ２Ｃｕ３Ｏ７－δ（ＹＢＣＯ）超导薄膜后，制备出台阶结和射频超导量子干涉器（ｒｆＳＱＵＩＤ）．液氮中器件的磁通灵敏度和磁场灵敏度分别达到２．０×１０－４Φ０／Ｈｚ和２９４ｆＴ／Ｈｚ．涂有真空导热硅脂作保护层的器件，至今寿命已达１０个月，经历了３０次以上（个别器件达５０次）测试过程中从液氮到室温的冷热循环，性能没有明显的变化，表现出很好的稳定性．通过研究，解决了制备ｒｆＳＱＵＩＤ器件工艺过程中存在的一些问题，提高了制备器件的可重复性，得到高性能器件的成品率达到３０％～５０％．Abstract YBa 2Cu 3O 7- x (YBCO) grain boundary junction and rf Superconducting Quantum Interference Devices (SQUID) have been prepared on SrTiO 3 and LaAlO 3 (001) substrates with a ditch type step by single layer technology. The magnetic field noise and flux noise level of these bare SQUIDs have been 2.0×10 -4 Φ 0/Hz and 294fT/Hz at 77K and white noise range respectively. After improving the electronic circuit, the noise level goes up to 7×10 -5 Φ 0/Hz and 100fT/Hz respectively. These SQUIDs covered with Silicone Oil have indicated a good stability. No much change could be observed after keeping in a desiccator for more than 10 months and undergoing more than 30 cycles from room temperature to liquid nitrogen temperature in measurement.

关 键 词：性能 SQUID 制备 YBCO 沟槽型 台阶结 超导体 

分 类 号：TM262.05[一般工业技术—材料科学与工程] O511.1[电气工程—电工理论与新技术]