Superconducting thin films were prepared on single crystal LaAlO3 (001) substrates by using a chemical vapour deposition technique. Firstly, B precursor films were grown onto LaAlO3 (001) substrates by chemical vapour deposition; using B2H6 as a B source. The Mg was then incorporated into the films during post-annealing (890C, 40min) in the presence of high-purity bulk Mg. The resultant MgB2 films on LaAlO3 substrates exhibited a random orientation, with dense and well-formed grains in the films. Resistance and direct-current magnetization measurements of the films revealed a sharp superconducting zero resistance transition temperature of 37.5K, while magnetization hysteresis measurements yielded a critical current density of 2.6 x 107A/cm2 at 15K in zero field.

Preparation and Properties of MgB2 Thin Films on LaAlO3 Substrates by Chemical Vapour Deposition. S.F.Wang, Y.L.Zhou, Y.B.Zhu, Z.Liu, Q.Zhang, Z.H.Chen, H.B.Lu, S.Y.Dai, G.Z.Yang: Superconductor Science and Technology, 2003, 16, 748-51