Thermal isolation of high-temperature superconducting thin films using silicon wafer bonding and micromachining

Using a new micromachining technology, thermally isolated thin films of high-temperature superconductor have been microfabricated. The intended application for these structures is in infrared bolometers. A silicon wafer bonding process produces a low thermal mass island of single-crystal silicon on a silicon nitride membrane which provides thermal isolation. The silicon can act as a seed for the epitaxial growth of YBa₂Cu₃O₇ on a yttria-stabilized zirconia buffer layer. This paper describes the overall concept of the thermally isolated device, and demonstrates that the micromachined structure can be fabricated with high-quality superconducting films