Electrophoretic deposition of textured YBa2Cu3O7−x films on silver substrates

We have deposited 10–20‐μm‐thick YBa2Cu3O7−x films by an electrophoretic process on silver substrates in a magnetic field of 8 T. X‐ray diffraction patterns of these 2.4‐cm‐diameter samples show a high degree of c‐axis texturing perpendicular to the surface. Their microwave surface resistance Rs was measured at 21.5 GHz in the temperature range from 4.2 to 300 K. It was found to drop sharply at 92.4 K to reach 18±3 mΩ at 77 K and less than 3 mΩ at 4.2 K. These first results exceed the values obtained from bulk samples and untextured thick films, and are lower than Rs of pure copper at the same frequency and temperature. The electrophoretic deposition technique is applicable to large substrates of nonplanar geometry and is therefore suitable for applications of high‐Tc superconductors in the field of microwave technology.