Experimental and theoretical study of the thermal solubility of the vacancy in germanium

Quenching experiments are performed using state of the art p-type Czochralski-grown Ge samples. The vacancy formation energy and thermal equilibrium concentration are determined on the basis of resistivity changes measured after quenching, using van der Pauw and Hall measurements. The results are compared with previously published experimental data and with results from analytical and ab initio calculations of the formation energy of the vacancy in different charge states. The deep levels introduced during the quenching step are studied with deep level transient spectroscopy and with FTIR, revealing besides the typical quenching related defects which are probably connected with vacancies also the presence of Cu.