SEMICONDUCTOR SWITCHING ELEMENT

A trench gate semiconductor switching element is provided. The semiconductor substrate of the element includes a second conductivity type bottom region in contact with the gate insulation layer at a bottom surface of the trench, and a first conductivity type second semiconductor region extending from a position in contact with a lower surface of the body region to a position in contact with a lower surface of the bottom region. The bottom region includes a first bottom region in contact with the gate insulation layer in a first range of the bottom surface positioned at an end in a long direction of the trench and extending from the bottom surface to a first position; and a second bottom region in contact with the gate insulation layer in a second range adjacent to the first range and extending from the bottom surface to a second position lower than the first position.