High-Quality YBa2Cu3O7−x Films with CeO2/YSZ Buffer Layers on 2-Inch Si Wafers Deposited by Pulsed Laser

The pulsed laser deposition (PLD) process is shown for in situ reproducibly fabricating YBa2Cu3O7−x (YBCO) superconducting films with yttrium-stabilized zirconia (YSZ) and CeO2 buffer layers, nonsuperconducting crystalline YBa2Cu3O7−x (YBCO*) passivation layer, and silver contact film on 2-inch silicon wafers. Variations of less than ±7% in film thickness have been obtained for this multilayer growth over the whole wafer. The YBCO films on 2-inch silicon wafers have homogeneous superconducting properties with zero resistance temperature Tc0 from 88.4 K to 88.9 K. and critical current density Jc at 77 K and zero field from 2.5 × 106 to 7× 106 A/cm2. The YSZ, CeO2 and YBCO layers grow epitaxially on silicon wafers. Full widths at half maximum (FWHMs) of (113) reflections of 40 nm thick YBCO layer from φ-scan patterns are only 1.71° and 1.85° corresponding to the center and edge of the wafer, respectively. These results are very promising for developing high-quality high-Tc superconducting devices on large-area silicon wafers.