Device degradation caused by gateoxide damage in a FinFET on silicon-on-insulator is recovered using punchthrough current via a silicon fin. As the high level of drain current flows under a punchthrough mode, localized Joule heat driven by drain current, enough to anneal the gate oxide, is induced in the channel. This selectively cured localized damage in the FinFET. The dependence of recovery on the gate length, substrate material underneath the channel, and the proper range of annealing voltage are investigated.