Open AccessGrowth of Epitaxial MgB 2 Thick Films with Columnar Structures by Using HPCVD
Author(s) -
Seong W. K.,
Huh J. Y.,
Kang W. N.,
Kim J.W.,
Kwon Y.S.,
Yang N.K.,
Park J.G.
Publication year - 2007
Publication title -
chemical vapor deposition
Language(s) - English
Resource type - Journals
eISSN - 1521-3862
pISSN - 0948-1907
DOI - 10.1002/cvde.200706636
Subject(s) - materials science , epitaxy , transmission electron microscopy , susceptor , planar , thin film , hexagonal crystal system , composite material , crystallography , nanotechnology , chemistry , layer (electronics) , computer graphics (images) , computer science
Epitaxial MgB 2 thick films are grown on Al 2 O 3 substrates at 600 °C by using the hybrid physical (HP)CVD technique. In order to obtain a high magnesium vapor pressure around the substrates, we use a special susceptor having a susceptor cap and achieve a very high growth rate of 0.17 μm min –1 . Hexagonal‐shaped columnar structures are observed by cross‐sectional and planar‐view transmission electron microscope (TEM) images. For the 1.7 μm thick film, the T c is observed to be 40.5 K with a J c of 1.5 × 10 6 A cm –2 at 30 K. The vortex pinning mechanism by intercolumnar boundaries will be discussed.