van der Pauw method

The van der Pauw method is a technique used to measure the electrical resistivity or conductivity of a flat, thin, and uniformly shaped material. It involves placing four small contacts on the edges of the sample, then passing a small current through two contacts and measuring the voltage across the other two. By repeating these measurements in different configurations, it accounts for the shape and contact placement, allowing precise calculation of the material’s resistivity without needing to know its exact dimensions. This method is widely used because it is accurate, adaptable, and requires only simple equipment.