Electrical characterization of the influence of the annealing energy density on carrier lifetimes in Germanium

In this work the authors examine the influence of the annealing energy density on carrier lifetime of n⁺/p Ge diodes processed by laser thermal annealing (LTA) and rapid thermal annealing (RTA). Current-voltage and capacitance-voltage measurements have been performed, and subsequently the reverse current and capacitance were separated into bulk and peripheral components to extract carrier lifetime: this allows the estimation of the bandgap position of the generation-recombination centres. The results indicate that the generation lifetime increases with increasing laser anneal energy density, coinciding with better crystal quality.