New crucible made of Y2O3 for preparing yttrium based high T c superconducting films by molecular beam epitaxy

Abstract
A new kind of crucible made of Y2O3 has been used for the first time to evaporate yttrium for the preparation of YBa2Cu3O7−y films by MBE. Problems related to the purity and thermal stability of the crucible and the evaporating stability of yttrium were investigated. The results imply that this crucible can be used for yttrium evaporation. Purity was high and the evaporating stability was good in spite of some interdiffusion and reaction between Y and Y2O3. YBa2Cu3O7−y films with Tcon of 77 K and Tco of 52 K have been obtained in situ using this crucible.