In-situ patterning and critical current density measurements in laser deposited high-Tc superconducting thin films

The authors have performed transport critical current density, Jc, measurements on epitaxial superconducting thin films which were in-situ patterned during the laser deposition process. Shadow masks of various dimensions were placed close to the substrate to generate different patterns. Epitaxial films of YBa2Cu3O7 on (100) SrTiO3, (100) YSZ, and (100 LaAlO3 substrates were fabricated at low processing temperatures (500--650 degrees C) by the biased laser deposition technique in an oxygen ambient of 200 mtorr. Excellent quality superconducting thin films were formed on patterned areas. The critical temperature of the films were found to be in the range of 88 to 90 K, and the best critical current density values (at 77 K, and zero magnetic field) greater than 6.5 x 106 Amps/cm2 were obtained for silver doped YBa2Cu3O7 films on (100) LaAlO3 substrates