A thin film technology compatible with multilayer device fabrication is critical for exploring the potential of the 39-K superconductor magnesium diboride for superconducting electronics. Using a Hybrid Physical-Chemical Vapor Deposition (HPCVD) process, it is shown that the high Mg vapor pressure necessary to keep the MgB2 phase thermodynamically stable can be achieved for the {\it in situ} growth of MgB2 thin films. The films grow epitaxially on (0001) sapphire and (0001) 4H-SiC substrates and show a bulk-like Tc of 39 K, a Jc(4.2K) of 1.2×107 A/cm2 in zero field, and a Hc2(0) of 29.2 T in parallel magnetic field. The surface is smooth with a root-mean-square roughness of 2.5 nm for MgB2 films on SiC. This deposition method opens tremendous opportunities for superconducting electronics using MgB2.
@article{arxiv.cond-mat/0203563,
title = {In situ epitaxial MgB2 thin films for superconducting electronics},
author = {X. H. Zeng and A. V. Pogrebnyakov and A. Kotcharov and J. E. Jones and X. X. Xi and E. M. Lysczek and J. M. Redwing and S. Y. Xu and Qi Li and J. Lettieri and D. G. Schlom and W. Tian and X. Q. Pan and Z. K. Liu},
journal= {arXiv preprint arXiv:cond-mat/0203563},
year = {2009}
}