Abstract: This GTO thyristor comprises: (i) a cathode layer that is divided into a large number of cathode-layer fingers, (ii) a gate layer contiguous with the fingers, with a PN junction J1 between each finger and the gate layer, (iii) a cathode electrode on each finger, and (iv) a gate electrode on the gate layer having portions surrounding the fingers disposed in spaced relation to the fingers. Turn-off of the GTO thyristor is effected by forcing a turn-off current to flow between the cathode electrode of each finger and the gate electrode through the associated PN junction J1. This PN junction at each finger has a centrally-located region that is characterized by an avalanche voltage that is substantially lower than the avalanche voltage that characterizes this junction in the region of the junction surrounding the centrally-located region, and this relatively lower avalanche voltage enhances the current turn-off capabilities of the GTO thyristor.