To provide an antifuse element comprising a gate electrode, a depletion channel region, a gate insulating film between the gate electrode and the channel region, and a diffusion layer region forming a junction with the channel region. An end of the gate electrode coincides substantially with a boundary between the channel region and the diffusion layer region as seen from a planar view, and is formed in a zigzag configuration. The end of the gate electrode is longer than the end with linear configuration and the end of the gate insulating film is likely to be subjected to breakdown.