OPTIMIZATION OF THE PROPERTIES OF HIGH-T-C THICK-FILMS

High-T-c thick films of YBa2Cu3O7-partial derivative (YBCO) are potent ially useful in various applications; for example in practical fault c urrent limiters in the field of power engineering, The material also s hows promise in the fabrication of numerous microwave devices, However it is of paramount importance to optimise their microstructure and pr operties, with particular respect to the critical current density (J(c )) and surface resistance (R-s), Doping and barrier layer technology h ave been used to improve the characteristics of the films, Enhanced cu rrent carrying capacity is achieved as a result of doping with Pt and a Ba4Cu1+xPt2-xO9-z (0412) compound Exploitation of low dielectric los s and economically attractive alumina substrates has also been achieve d, by means of barrier layers, The relation between the processing, mi crostructure and superconducting behaviour is reported.