The slow positron beam technique -: A unique tool for the study of vacancy-type defects in semiconductors

Positron annihilation has been established as a unique tool for the identification of open-volume defects in semiconductors. In particular, the slow-positron beam technique allows the characterization of defects in the near-surface region and in thin epitaxial layers. This ability is demonstrated with the help of three examples: ion-implantation induced defects in silicon, defect-rich low-temperature-grown (LT) GaAs layers, and near-surface defects introduced by saw-cutting of GaAs wafers by a diamond wheel.