Patent ID: 9252261
Filing Date: 2016-02-02
CPC Classification: H01L

Claim Text:
1. A semiconductor device comprising: a semiconductor substrate; a drift region of first conductivity type formed on one of main surfaces of the semiconductor substrate; a well region of second conductivity type formed in the drift region; a source region of first conductivity type formed in the well region; a trench with a depth penetrating the source region and the well region and reaching the drift region; a gate electrode formed on a side portion of the trench while interposing a gate insulating film therebetween; a source electrode connected to the well region and the source region; a drain electrode connected to other of the main surfaces of the semiconductor substrate; an interlayer insulating film that is formed on the gate electrode and coats the gate electrode; an anode region formed on a bottom portion of the trench or in the drift region immediately under the trench; a contact hole formed in the trench at a depth reaching the anode region; and an inner wall insulating film formed on an inner wall side surface of the contact hole while being in contact with the gate electrode, wherein the source electrode is embedded in the contact hole while interposing the inner wall insulating film between the source electrode and the gate electrode, and is electrically connected to the anode region in a state of being insulated from the gate electrode by the inner wall insulating film, and a plurality of contact holes is formed discretely in the trench with respect to a main surface direction of the semiconductor substrate, and a width of the trench at portions in which the contact holes are formed is wider than a width of the trench at portions in which the contact holes are not formed.