Van Der Pauw Measurements of Resistivity in Plastic/Metal Composites

Abstract
The van der Pauw (VdP) technique provides a four-probe measurement of a sample's average resistivity. It is generally applied to samples which have a uniform density and thickness but an arbitrary shape. We apply the VdP method to a metal/plastic composite. Samples are cut into rectangular shapes, but internally the metal structure is a random shape. Values of resistivity correlate well (> 90%) to values measured by a two-probe technique. We can determine a composite's structure in a highly accurate though destruc tive manner. Some in-situ test applications are proposed.