  To investigate the superconducting properties of iron pnictides we prepared
planar hybrid SNS' junctions in thin film technology with a pnictide base
electrode, a gold barrier layer and a lead counter electrode. Our design allows
characterization of the electrodes and the junction independently in a 4-probe
method. We show how both electrodes influence the measured spectra due to their
spreading resistance. While the Pb electrode has a constant resistance above
its $T_c$, the contribution of the pnictide electrode is clearly
current-dependent and thus it needs a more advanced method to be corrected. We
present an empirical method, which is simple to apply and allows to deal with
the spreading resistance in our junctions to recalculate the actual conductance
and voltage of one junction at given temperature.
