A measurement of a minority-carrier lifetime in a p-type silicon wafer by a two-mercury probe method

A simple evaluation technique of a lifetime τ and diffusion coefficient D of minority carriers in a semiconductor wafer by using the newly contrived two-mercury probe method and a graphic analysis is described. The two-mercury probe method makes it possible to measure τ and D in an electrode-free wafer sample. The graphic analysis can be applied to a semiconductor wafer with a large backsurface recombination velocity for evaluation of τ and D. Using the proposed technique, the minority-carrier lifetime and diffusion coefficient have been successfully evaluated even in a p-type low-resistivity (0.2–0.5 Ω cm) silicon wafer for the first time.