A Copper-Related Shallow Acceptor in Quenched Germanium

Abstract
The temperature variation of hole density was measured in the range 5–200 K after successive annealings at 320°C. It was found that a shallow acceptor at E v+9 meV disappears on annealing, being replaced by a just equal additional density of substitutional copper. This provides experimental proof that the shallow acceptor is a defect complex containing at least one copper atom.