A structure is provided that ensures a low on-resistance and a better blocking
effect. In a lateral type SIT (Static Induction Transistor) in which a first region
is used as a p+ gate and a gate electrode is formed on the bottom of
the first region, the structure is built such that the p+ gate and an
n+ source are contiguous. An insulating film is formed on the surface
of an n- channel, and an auxiliary gate electrode is formed on the insulating
film. In addition, the auxiliary gate electrode and the source electrode are shorted.
