Thermally-induced self-assembling nanotechnology of gold nano-dots on CeO2-buffered sapphire for superconducting films

A typical facility for fabrication of devices based on high temperature superconducting (HTS) films grown on the less-expensive CeO2-buffered sapphire substrates comprises a transfer chamber, a chamber for CeO2 growth, a chamber for YBa2Cu3Oy (YBCO) growth, and a chamber for Au deposition at room temperature. Here we present the adaptation of our previously-reported method to create artificial pinning centres in HTS films through self-assembled nano-scale islands for this type of facility without making any modifications. We succeeded to grow Au nano-dots from an ultra-thin layer of Au grown at room temperature subsequently annealed in the chamber for YBCO deposition, in the same conditions as for YBCO growth. AFM and RBS were used to investigate the formation of Au nano-dots, while XRD and susceptibility measurements were used to study the properties of nano-structured YBCO films.