Four-point probe method

The four-point probe method is a technique used to measure the electrical conductivity of materials. It employs four equally spaced metal probes that touch the surface of the material being tested. A current is passed through the outer probes, while the voltage is measured across the inner probes. This setup minimizes the effects of contact resistance and allows for a more accurate assessment of the material's intrinsic conductivity. It is commonly used in fields like electronics and materials science to evaluate the properties of semiconductors and thin films.