Abstract
We compare the superlattice modulation, microstructure, and epitaxy of Tl 2 Ba 2 Ca 2 Cu 3 O 1 0 thin films grown on MgO [100] and SrTiO 3 [100] substrates by dc diode sputtering. Films grown on MgO were found to be quite clean with the c axis perpendicular to the substrate. However, no in-plane orientational relationship to the substrate was found. Films grown on SrTiO 3 , on the other hand, showed very good epitaxy to the substrate despite the presence of second phases. Films grown on MgO also exhibited a longer coherence length of the superlattice modulation than those grown on SrTiO 3 under identical conditions.