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 Cu s 2− atoms and thermal electron emission from Cu s 3− atoms in plastically deformed Cu-doped n-type germanium. The activation energy E σ, the electron capture cross-section, the energy E 3 of the third acceptor level of Cu s/3− atoms, and the ionization entropy are determined. The lack of E 3-level broadening, the exponential capture kinetics for a filling-pulse duration of t p ≲ 1 ms, the fact that the Cu s/2−/3−-atom recombination parameters are independent of the dislocation density, and the low concentration of Cu s/2−/3− atoms in the deformed samples suggest that the DLTS spectra are due to Cu s/2−/3− atoms located outside the Read cylinders.