Properties of junctions using a-axis oriented Y-Ba-Cu-O films.

使用 a 轴取向 Y-Ba-Cu-O 薄膜的结的特性。

基本信息

批准号：
06650357
负责人：
KOBAYASHI Tadayuki
金额：
$ 1.34万
依托单位：
University of Electro-Communications.
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1995
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06650357/
关键词：
High Tc superconductor Thin film sputtering Tunnel junction 超伝導酸化物薄膜 a軸配向膜

项目摘要

Sandwich type SIN junctions of YBa<@D22@>D2Cu<@D23@>D2Ox(YBCO)/SrTiO<@D23@>D2(STO)/Au and YBCO/PrGaO<@D23@>D2(PGO)/Au were fabricated using a-axis oriented YBCO films under the some conditions using a rf magnetron sputtering with dc voltage biased substrate holder. The differential conductance-voltage(dI/dV-V) curves of junctions with defferent barrier thickness were investigated. The junction showed the tunnel-like behavior, though some junctions showed the curves with pinhole-short-circuits. The junctions had the change in the gradient of differential conductance in the curves at about (]SY.+-。[) 20mV.This change was obviously observed with decreasing the barrier thickness. On the other hand, it was also observed the small zero bias anomalies for the junctions with thin barrier. The curves of junctions with PGO barrier were simillar to those with the STO barrier. It is considered that the tunneling occurs via thin region in the ununiform barrier.And then, the effects of dI/dV-V curves on the heat treatment in oxygen gas were also investigated. In order to obtain the change in the gradient of dI/dV in the dI/dV-V curve, the optimum annealing time was 2-4h. The slope of the background conductance of junctions becomes steep with increasing the annealing time.

Sandwich type SIN junctions of YBa<@D22@>D2Cu<@D23@>D2Ox(YBCO)/SrTiO<@D23@>D2(STO)/Au and YBCO/PrGaO<@D23@>D2(PGO)/Au were fabricated using a-axis oriented YBCO films under the some conditions using a rf magnetic sputtering with dc voltage有偏的基板支架。研究了具有较低屏障厚度的连接处的差分电导电压（DI/DV-V）曲线。该交界处显示出类似隧道的行为，尽管一些连接处显示了带针孔短路的曲线。在约（]SY。+ - 。[）20MV的曲线中，连接的变化变化。显然观察到了这种变化，随着屏障厚度的降低。另一方面，还观察到了较薄的屏障连接处的零偏置异常。与PGO屏障的交界处的曲线相似，它们与具有Sto屏障的曲线相似。据认为，隧道通过不均匀屏障的薄区域发生。然后，还研究了DI/DV-V曲线对氧气中热处理的影响。为了获得DI/DV-V曲线中DI/DV梯度的变化，最佳退火时间为2-4H。随着退火时间的增加，连接的背景电导的斜率变成钢。