Fabrication of MgB2 thin film by rf magnetron sputtering

Abstract

Fabrication of superconducting MgB2 thin film on SrTiO3 and sapphire substrates by rf magnetron sputtering has been studied. We have tried both single target sputtering method using an Mg-excessive MgB2 target and co-sputtering of Mg and B. Argon sputtering pressure was 20 mTorr and 5% of hydrogen gas was added to trap the remanant oxygen gas in the deposition chamber. Films made by co-sputtering at room temperature followed by in situ annealing at 600 degreesC showed transition temperatures of about 24 K. However, those by single target sputtering or in situ co-sputtering showed either no superconducting transition or low T-c. (C) 2003 Elsevier Science B.V. All rights reserved.