Combinatorial sputtering in planetary type systems for alloy libraries with perpendicular gradients of layer thickness and composition realised by a timing approach

We present a combinatorial sputtering technique to fabricate alloy thin films with orthogonal gradients of thickness and stoichiometry in a planetary type sputtering system. Using this approach we prepared a library of planar Nb Josephson junctions with a magnetic compound layer made from Si and Fe on one wafer. The independent investigation of thickness and composition changes of the Fe \(_x\) Si \(_{1-x}\) layer allows the identification of transition regions where the phase difference of the superconducting order parameter across the barrier changes from 0 to \(\pi \) . A mapping technique which allows to identify the different coupling regimes depending on material properties might facilitate the fabrication of \(\pi \) junctions with tailored critical current, damping and normal resistance parameters for applications.