DLTS Study of plastically deformed copper-doped n-type germanium

Classical deep level transient spectroscopy (DLTS) and its modification are used to study the time constants of electron capture by substitutional Cus2− atoms and thermal electron emission from Cus3− atoms in plastically deformed Cu-doped n-type germanium. The activation energy Eσ, the electron capture cross-section, the energy E3 of the third acceptor level of Cus/3− atoms, and the ionization entropy are determined. The lack of E3-level broadening, the exponential capture kinetics for a filling-pulse duration of tp ≲ 1 ms, the fact that the Cus/2−/3−-atom recombination parameters are independent of the dislocation density, and the low concentration of Cus/2−/3− atoms in the deformed samples suggest that the DLTS spectra are due to Cus/2−/3− atoms located outside the Read cylinders.