requisite structure wherein the top and bottom surfaces will remain substantially free of intermetallic compound a minimum of routine experimentation will identify suitable combinations of the said materials for example to accomplish the aforesaid the sequential deposition of lead gold lead and indium will provide a layer in which the intermetallic compound in this case auin 2 is concentrated within the formed layer and no detectable amounts of auin 2 are present in the top surface and the resulting layer is suitable for fabricating the base electrode the amount of intermetallic compound former employed usually ranges from about 2 to about 10 by weight of the superconductor the use of large amounts does not provide appreciable advantage and will tend to reduce the superconduction of the layer the thicknesses of the resulting layer of superconductor and intermetallic compound can range from about 0 1 to about 1 micron preferably about 0 2 to about 0 4 micron using the inventive process the films produced thereby are suitable for device fabrication devices produced therewith exhibited in excess of one hundred times fewer failures during repeated thermal cycling in the range of 350 u00b0 to 4 2 u00b0 k the improved cyclability of the present devices is due to the fine grain size u2266 100 nm of the components of the metal films the films produced in accordance with the present process show good adhesion to the substrate and.