Influences of microstructure on critical current properties in MgB 2/Al Film

Yusuke Shimada, Yuuki Kubota, Satoshi Hata, Ken Ichi Ikeda, Hideharu Nakashima, Toshiya Doi, Takanori Fujiyoshi

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)


The metal Al is lighter in weight than other substrate materials for MgB2 films such as Si and Ni. This property inspires MgB2 fabrication on a large-scale Al substrate as a new route to MgB2 tapes. Here we report microstructural factors influencing critical current density, Jc, in MgB2/Al films. MgB2/Al films were prepared by the following steps: deposit a boron layer of 3 nm in thickness on an Al substrate heated at 280°C ; deposit Mg and boron on the boron layer (sample A). For comparison, Mg and boron were deposited directly on an Al substrate heated at 265°C (sample B). The microstructure was observed by transmission electron microscopy (TEM) and scanning TEM. Jc values at 20 K in the self-field were 4.9 × 106 A cm-2 for sample A and 2.7 × 106 A cm-2 for sample B. Both the samples form an oxygen-rich layer of 10 nm in thickness at the substrate surface. This oxygen-rich layer may suppress Al diffusion into MgB2 lattices. The [001] texture of columnar MgB2 crystals grown on the substrate is stronger in sample A than in sample B. This indicates that the boron layer deposition on the Al substrate is effective for fabricating well-textured MgB2 polycrystals, resulting in the higher J c enhancement for sample A.

Original languageEnglish
Article number6403883
JournalIEEE Transactions on Applied Superconductivity
Issue number3
Publication statusPublished - 2013

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Electrical and Electronic Engineering


Dive into the research topics of 'Influences of microstructure on critical current properties in MgB 2/Al Film'. Together they form a unique fingerprint.

Cite this