Semiconductor device for improving on voltage and saturation voltage
Provided is a semiconductor device including: a semiconductor substrate; gate trench portions; an emitter electrode; a mesa portion; an emitter region of a first conductivity type provided on an upper surface of the mesa portion and in contact with the gate trench portions; a contact region of a second conductivity type provided on the upper surface of the mesa portion; a base region of a second conductivity type provided below the emitter region and the contact region, in contact with the gate trench portions, and having a lower doping concentration than the contact region; a drift region of a first conductivity type provided below the base region and having a lower doping concentration than the emitter region; and a high resistance portion provided between the emitter electrode and the base region in a depth direction of the semiconductor substrate and having a higher resistance than the emitter region.
1 . A semiconductor device, comprising:
a semiconductor substrate;
a plurality of gate trench portions which are provided on an upper surface of the semiconductor substrate and extend along an extending direction;
an emitter electrode provided above the semiconductor substrate;
a mesa portion provided between adjacent gate trench portions out of the plurality of gate trench portions;
an emitter region of a first conductivity type, which is provided on an upper surface of the mesa portion and is in contact with the adjacent gate trench portions;
a contact region of a second conductivity type, which is provided on the upper surface of the mesa portion;
a base region of the second conductivity type, which is provided below the emitter region and the contact region in the semiconductor substrate, is in contact with the adjacent gate trench portions, and has a lower doping concentration than the contact region;
a drift region of the first conductivity type, which is provided below the base region in the semiconductor substrate and has a lower doping concentration than the emitter region; and
a high resistance portion which is provided between the emitter electrode and the base region in a depth direction of the semiconductor substrate and has a higher resistance than the emitter region,
wherein the emitter region and the high resistance portion are provided adjacent to each other in the depth direction,
wherein the emitter region and the contact region are arranged alternately in the extending direction,
wherein the emitter region includes a first high concentration emitter region, and
wherein the high resistance portion is a low concentration emitter region which is provided above the first high concentration emitter region and has a lower doping concentration than the first high concentration emitter region.
2 . The semiconductor device according to claim 1 , wherein
the plurality of gate trench portions each include a gate conductive portion, and
the gate conductive portion is provided on a lower side of a position at which the high resistance portion is provided in the depth direction of the semiconductor substrate.
3 . The semiconductor device according to claim 1 , wherein
the emitter region further includes a second high concentration emitter region which is provided above the low concentration emitter region and has a higher doping concentration than the low concentration emitter region.
4 . The semiconductor device according to claim 1 , wherein
the doping concentration of the low concentration emitter region is equal to or larger than the doping concentration of the base region.
5 . The semiconductor device according to claim 1 , wherein
the doping concentration of the low concentration emitter region is equal to or smaller than the doping concentration of the base region.
6 . The semiconductor device according to claim 1 , wherein
the doping concentration of the low concentration emitter region at a position in contact with the adjacent gate trench portions is higher than the doping concentration of the low concentration emitter region at a center of the mesa portion.
7 . The semiconductor device according to claim 1 , wherein
the base region includes:
a low concentration base region; and
a high concentration base region which is provided below the low concentration base region and has a higher doping concentration than the low concentration base region.
8 . The semiconductor device according to claim 3 , wherein
the doping concentration of the low concentration emitter region is equal to or larger than the doping concentration of the base region.
9 . The semiconductor device according to claim 3 , wherein
the doping concentration of the low concentration emitter region is equal to or smaller than the doping concentration of the base region.
10 . The semiconductor device according to claim 3 , wherein
the doping concentration of the low concentration emitter region at a position in contact with the adjacent gate trench portions is higher than the doping concentration of the low concentration emitter region at a center of the mesa portion.
11 . The semiconductor device according to claim 4 , wherein
the doping concentration of the low concentration emitter region at a position in contact with the adjacent gate trench portions is higher than the doping concentration of the low concentration emitter region at a center of the mesa portion.
12 . The semiconductor device according to claim 5 , wherein
the doping concentration of the low concentration emitter region at a position in contact with the adjacent gate trench portions is higher than the doping concentration of the low concentration emitter region at a center of the mesa portion.
13 . The semiconductor device according to claim 2 , wherein
the base region includes:
a low concentration base region; and
a high concentration base region which is provided below the low concentration base region and has a higher doping concentration than the low concentration base region.