Semiconductor device

A semiconductor device comprising:

• a semiconductor substrate having a first conductivity-type drift region;
• a transistor portion provided in the semiconductor substrate;
• and
• a diode portion provided in the semiconductor substrate, wherein
• the transistor portion has a second conductivity-type collector region provided between a lower surface of the semiconductor substrate and the drift region,
• the diode portion has:
• a cathode region that is provided between the lower surface of the semiconductor substrate and the drift region and has a doping concentration higher than that of the drift region;
• and
• a second conductivity-type floating region provided between the drift region and the cathode region,
• in a plane parallel with the lower surface of the semiconductor substrate, a distance from a boundary position between the collector region and the cathode region to an end portion position of the floating region that is closest to the boundary position is shorter than a width of the floating region in a straight line direction linking the boundary position and the end portion position,
• the diode portion has an opening region not provided with the floating region at the same depth position as the floating region, and
• a distance from the boundary position between the collector region and the cathode region to the end portion position of the floating region that is closest to the boundary position is shorter than at least one of a width of the opening region in the straight line direction linking the boundary position and the end portion position and a width of the opening region in a direction perpendicular to the straight line direction in the plane parallel with the lower surface of the semiconductor.

A semiconductor device comprising:

• a semiconductor substrate having a first conductivity-type drift region;
• a transistor portion provided in the semiconductor substrate;
• and
• a diode portion provided in the semiconductor substrate, wherein
• the transistor portion and the diode portion each have:
• a second conductivity-type base region provided in the semiconductor substrate and above the drift region;
• a plurality of trench portions that are provided penetrating the base region from an upper surface of the semiconductor substrate and have conductive portions provided therein;
• and
• a mesa portion sandwiched by trench portions,
• the transistor portion has one or more first conductivity-type accumulation regions that are provided in each of the mesa portions and between the base region and the drift region and have doping concentrations higher than that of the drift region,
• the diode portion has one or more first conductivity-type high concentration regions that are provided in each of the mesa portions and between the base region and the drift region and have doping concentrations higher than that of the drift region, and
• in at least one of the mesa portions of the transistor portion, the number of the accumulation regions formed in a depth direction is greater than the number of the high concentration regions formed in a depth direction in the mesa portion of the diode portion.