Qualitative comparison of calculated local currents along the test structure a) in the upper (black) and lower (red) ribbon for Sn₆₀Pb₄₀-solder (filled symbol) and used ECA (empty symbol). In b) the corresponding calculated current through the contact layer (from the upper into the lower ribbon) is shown in blue color. The schematic sample is drawn above the  graphic as a guide to the eye whereas the arrows in the scheme point at the ribbons and the contact material.