Semiconductor device

A semiconductor device, comprising:

• a body region of a first conductivity type formed on a main surface of a semiconductor substrate;
• a source region of a second conductivity type formed on a surface of the body region;
• a drift region of the second conductivity type formed to be in contact with the body region;
• a drain region of the second conductivity type formed on the drift region;
• a gate electrode formed on the body region between the source region and the drift region and the drift region on the side of the source region via a gate insulating film;
• a first field plate extending from the gate electrode in a direction of the drain region and formed on the drift region via a first insulating film;
• a second field plate composed of a plurality of wiring layers, and being in contact with the source region or the gate electrode and formed on the first field plate via a second insulating film;
• a first buried region of the first conductivity type being in contact with the body region and formed under the drift region;
• and
• a second buried region of the first conductivity type being adjacent to the first buried region and having an impurity concentration smaller than an impurity concentration of the first buried region formed under the drift region and extending in the direction of the drain region,
• wherein in the plurality of wiring layers constituting the second field plate, a distance between an upper wiring layer and the drain region is shorter than a distance between a lower wiring layer and the drain region, and a distance between a lowermost wiring layer and the drain region is shorter than a distance between the first field plate and the drain region,
• a distance between an uppermost wiring layer and the drain region is shorter than a distance between the second buried region and the drain region, and
• the distance between the first field plate and the drain region is longer than a distance between the first buried region and the drain region.