DocumentCode :
1542122
Title :
Interfacial microstructures in ramp type multilayer Josephson junctions studied by TEM
Author :
Gao, J. ; Yang, Y. ; Sun, J.L.
Author_Institution :
Dept. of Phys., Hong Kong Univ., Hong Kong
Volume :
9
Issue :
2
fYear :
1999
fDate :
6/1/1999 12:00:00 AM
Firstpage :
3145
Lastpage :
3148
Abstract :
The microstructures of high T/sub c/ ramp type Josephson junctions were studied by using transmission electron microscopy. The work was emphasized at the interfacial defects and the influence of the ramp slope. The results show that for the ramp slope angles of 15/spl deg//spl sim/40/spl deg/, the epitaxy was still remained through all layers at the ramp region without the formation of big grain boundaries. No amorphous layers and secondary phases were observed at the barrier interfaces. For a gentle ramp junction, small misoriented grains appeared in some portions of the barrier. The substrate ramp formed during the ion etching process had little influence on the growth of the upper layers. In junctions with a steep ramp, defects increased near the interface, although the epitaxy of the barrier was of good quality. The results demonstrate that the slope angle of the junction ramp is an important factor that influences the performance of the Josephson junctions.
Keywords :
Josephson effect; high-temperature superconductors; sputter etching; superconducting epitaxial layers; transmission electron microscopy; epitaxial thin film; high T/sub c/ superconductor; interfacial defects; interfacial microstructure; ion etching; ramp type multilayer Josephson junction; slope angle; transmission electron microscopy; Argon; Epitaxial growth; Ion beams; Josephson junctions; Microstructure; Nonhomogeneous media; Physics; Substrates; Sun; Transmission electron microscopy;
fLanguage :
English
Journal_Title :
Applied Superconductivity, IEEE Transactions on
Publisher :
ieee
ISSN :
1051-8223
Type :
jour
DOI :
10.1109/77.783696
Filename :
783696
Link To Document :
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