CHEMICAL-VAPOR-DEPOSITION OF YBA2CU3O7-X PRBA2CU3O7-X HETEROSTRUCTURES/

A reactor which allows chemical vapor deposition from metalorganic pre cursors (MOCVD) has been specially designed to synthesize alternate la yers of ''superconductor/insulator'' type. The YBa2Cu3O7-1/PrBa2Cu3O7- x studied system is suitable for heteroepitaxial multilayer structures . Thin films, deposited between 750 and 900-degrees-C on MgO {100}, Sr TiO3 {100} and LaAlO3 {012} are obtained by thermal decomposition of p recursors (tetramethylheptanedionates of Y, Ba, Pr and Cu). YBa2Cu3O7- x layers grown in this reactor have critical current densities of some 10(6) A. cm-2 at 77 K. The temperature dependence of resistivity in t he PrBa2Cu3O7-x films shows semiconducting behavior. Growth temperatur e effect on the interdiffusion at the multilayer interfaces will be st udied in the case of two samples elaborated at different temperatures of deposition (750 and 900-degrees-C). Although the element diffusion becomes larger with the temperature of deposition, the superconducting properties are not damaged.