Aging of superconducting Y₁Ba₂Cu₃O_7−x structures on silicon Available to Purchase

The long‐term stability of epitaxial thin film structures of superconducting Y₁Ba₂Cu₃O_7−x on silicon wafers (100), using a yttria‐stabilized ZrO₂(YSZ) buffer, is presented and compared to identical structures on SrTiO₃ (100) and yttria‐stabilized ZrO₂ (100) single crystals. For Y₁Ba₂Cu₃O_7−y/YSZ/Si heterostructures, the maximum Y₁Ba₂Cu₃O_7−y film thickness is limited to 50 nm; otherwise thermal strain induces microcracks. Thinner films are more stable, but nevertheless show aging over several weeks, which affects critical current density and room‐temperature resistivity, but not the critical temperature T_c.