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arXiv · 0709.1884

Growth of Epitaxial MgB2 Thick Films with Columnar Structures by Using HPCVD

Won Kyung Seong·Ji Yeong Huh·Won Nam Kang·Jeong-Woon Kim·Yong-Seung Kwon·Nam-Keun Yang·Je-Geun Park
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Abstract

Epitaxial MgB2 thick films were grown on Al2O3 substrates at 600 oC by using the hybrid physical chemical vapor deposition (HPCVD) technique. In order to obtain a high magnesium vapor pressure around the substrates, we used a special susceptor having a susceptor cap and achieved a very high growth rate of 0.17 um/min. Hexgonal-shaped columnar structures were observed by cross-sectional and planar view transmission electron microscope (TEM) images. For the 1.7-um-thick film, the Tc was observed to be 40.5 K with a Jc of 1.5 x 10^6 A/cm^2 at 30 K. The vortex pinning mechanism by intercolumnar boundaries will be discussed.

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Won Kyung Seong, Ji Yeong Huh, Won Nam Kang, Jeong-Woon Kim, Yong-Seung Kwon, Nam-Keun Yang, Je-Geun Park. 2007-09-12. Growth of Epitaxial MgB2 Thick Films with Columnar Structures by Using HPCVD. https://arxiv.org/abs/0709.1884

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