PURPOSE: To prevent a thyristor element from damaging by providing different lifetimes of carriers of a base region of the elements, and uniformly disposing them, thereby effectively dispersing a main current.

CONSTITUTION: In a GTO thyristor, a buried gate layer P+ formed on a sub strate is formed in a structure that slit-shaped through hole regions H1, H2 of the same width are aligned uniformly in parallel and the lifetimes of minority carriers of a base layer n- projected with the regions H1, H2. With the thus construction, a thyristor element having a layer n- of shorter lifetime at turning OFF time is early turned OFF from a thyristor element having a layer n- of longer lifetime, a main current is dispersed to the element of the layer n- having longer lifetime, and eventually turned OFF in the element. In other words, a current is not concentrated at partial element having the region H2 to prevent the element from damaging.