Abstract
Carrier mobility is often used to evaluate semiconductor material. A low value of mobility is generally construed to imply the presence of impurities or defects that adversely affect carrier transport. It is shown theoretically that low mobility values will also be obtained by van der Pauw measurements on samples containing certain types of radial inhomogeneities in the distribution of ionized impurities. The theoretical predictions have been confirmed by experiments on germanium slices cut from Czochralski‐grown crystals.