Donor Complexes Formed by Cu and Zn Multi-Acceptor Impurities in Ge Crystals

Abstract―Based on Hall effect measurements it is shown that quenching of complexly doped Ge〈Zn,Сu〉 crystals at 1070–1100 K leads to the formation of additional electrically active donor centers with activation energy Еd = Еc – 93 meV in them. Further annealing of crystals at 550–570 K leads to disappearance of these centers. The most likely model of additional deep donor centers is a complex consisting of a pair of substituent zinc atoms (Zns) and interstitial copper atoms (Cui). The necessity of taking into account the formation of additional donor centers in precise doping Ge〈Zn〉 crystals with copper by the method of decomposition of supersaturated solution of impurity in matrix is demonstrated.