Growth of (YBaCuO)m/(PrBaCuO)n Superlattices by MOCVD

Abstract

[(YBaCuO) m /(PrBaCuO) n ] 10 multilayers have been deposited by Metal Organic Chemical Vapor Deposition (MOCVD). The films grow on SrTiO 3 (100) and MgO (100) substrates and have c-axis perpendicular to the substrate. A serie of superlattices has been synthesised with different deposition temperatures ranging between 700 and 850°C with different modulations (the thickness of YBCO layers staying unchanged and equal to 100A). The elements concentrations profiles at the interfaces and the interdiffusion were determined by secondary neutral mass spectroscopy (SNMS). X-ray diffraction show satellite peaks (characteristic of superlattice modulation) around 001 and 002 reflections. Moreover, the samples show a good in-plane orientation. The superconducting properties are analysed by AC screening. The critical temperature reaches 88K in the case of m=8 and n=2 (n and m being the numbers of units cells along c-axis for YBCO layer and PBCO one respectively).