High Temperature Superconductor Device Stencil
Original Publication Date: 1985-Aug-01
Included in the Prior Art Database: 2005-Feb-19
Fabrication of superconducting devices with high transition temperatures (10 to 25ŒK) is presently restricted to A15-type compounds, such as Nb3Sn, Tc=18K, or NbN, Tc=16K, for example. These materials have very short superconducting coherence lengths, typically on the order of 50 angstroms, and for tunneling applications, these films must be of excellent quality right up to the surface since it is the top coherence length of the material that determines the tunneling characteristics. In addition, the superconducting properties are sensitive to both the stoichiometry and crystallographic order. To obtain good order in these materials, deposition at elevated temperatures, 600 to 1000ŒC is required.