Title :
Cross-sectional TEM observation of Nb/AlOx-Al/Nb junction structures
Author :
Imamura, T. ; Hasuo, S.
Author_Institution :
Fujitsu Lab. Ltd., Atsugi, Japan
fDate :
3/1/1991 12:00:00 AM
Abstract :
A study of the microstructure of Nb/AlOx-Al/Nb Josephson junctions by cross-sectional transmission electron microscopy (TEM) yielded information regarded the junction barrier region. Both thick Nb and several-nanometer Al form polycrystalline films with columnar structures. Nb is oriented to the (110) plane, and Al to the (111) plane. The 200-nm lower Nb has a wavy surface with -5-nm smoothness, but its surface is planarized by several-nanometer Al deposited on it. Thus, AlOx with a smoothness under 1 nm can be formed on Al. The upper Nb has a good crystalline structure, even just above the AlOx barrier
Keywords :
aluminium; aluminium compounds; niobium; superconducting junction devices; transmission electron microscope examination of materials; Josephson junctions; Nb-AlOx-Al-Nb; columnar structures; cross sectional TEM; crystalline structure; junction barrier region; junction structures; microstructure; smoothness; Artificial intelligence; Crystallization; Electrodes; Grain size; Microstructure; Niobium; Sputtering; Transmission electron microscopy; Tunneling; Voltage;
Journal_Title :
Magnetics, IEEE Transactions on
