The minority carrier recombination lifetimes of ultraviolet-irradiated silicon wafers were studied using the laser-microwave photoconductance method. These wafers were intentionally surface contaminated with metals. With ultraviolet irradiation, the effective minority carrier recombination lifetimes of these samples are enhanced. The Lifetime enhancement occurs at a faster rate for contaminated wafers. These lifetime enhancements are not permanent; with cessation of the ultraviolet radiation, the preirradiation levels can be restored.