Characteristics of Interface-Modified Josephson Junctions Fabricated under Various Etching Conditions
Characteristics of Interface-Modified Josephson Junctions Fabricated under Various Etching Conditions
复制标题
不同蚀刻条件下制备的界面改性约瑟夫森结的特性
DOI:
10.1143/jjap.39.l284
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发表时间:
2000
期刊:
影响因子:
--
通讯作者:
H. Hayakawa
中科院分区:
文献类型:
--
作者:
M. Horibe;Y. Inagaki;Kazuhiro Yoshida;Gen;N. Hayashi;A. Fujimaki;H. Hayakawa
We have studied the influence of process parameters on electrical properties for interface-modified junctions (IMJs) based on YBa2Cu3Ox. Tunnel barriers are produced by an electron cyclotron resonance (ECR) plasma etching process and subsequent vacuum annealing. We have found that time and accelerating voltage (Vacc) in the etching sequence, in which the ramp-edge geometry is defined, are very important parameters for the barrier formation. Increasing the etching time and accelerating voltage lead to the reduction of critical current densities. By setting these parameters at appropriate values, we can control the critical current of the IMJs. We have also found that the IMJs with high junction resistance, which are fabricated at higher accelerating voltages above 700 V, have transport mechanisms via localized states for quasi particles. The X-ray photo spectroscopy analysis suggests that accelerating voltages above 700 V enhance the thickness of the barrier, while those below 700 V affect both barrier resistivity and thickness.