SEMICONDUCTOR DEVICE
A semiconductor device relating to the present invention comprises a base layer of an N-type impurity region. In the base layer, trenches are provided. In the each trench, a gate insulating film and a gate electrode are formed. A body layer of a P-type impurity region is formed in contact with the trenches, and in parallel adjacent to the base layer. On the main surface of the body layer, an emitter layer of an N-type impurity region is provided. On the main surface of the body layer, a contact layer of a P-type impurity region is provided spaced from the trenches. The emitter layer and the contact layer are exposed in different regions on the main surface of the body layer. A buried layer of a P-type impurity region is formed spaced from the trenches in closer to the base layer than to the contact layer in the body layer.
1 . A semiconductor device including an insulated gate bipolar transistor, comprising:
a base layer of a first conductivity type impurity region;
a trench formed region formed within the base layer;
a gate insulating film and a gate electrode formed within the trench formed region;
a body layer of a second conductivity type impurity region formed in contact with the trench formed region within the base layer;
an emitter layer of the first conductivity type impurity region formed on a main surface of the body layer;
a contact layer of the second conductivity type impurity region formed spaced from the trench formed region on the main surface of the body layer; and
a buried layer of the second conductivity type impurity region formed spaced from the trench formed region in the body layer, and an impurity concentration peak position of the buried layer is deeper than an impurity concentration peak position of the contact layer.
2 . A semiconductor device according to claim 1 , wherein the buried layer is provided in a state that a breakdown voltage of a PN junction composed of the body layer wherein the buried layer is formed and the base layer is lower than a breakdown voltage between a bottom corner of the trench formed region formed within the base layer and the base layer.
3 . A semiconductor device according to claim 1 , wherein, in plane view of the main surface, a plurality of the trench formed regions is disposed spaced from one another;
the contact layer is disposed in each space between the trench formed regions without intersecting with the trench formed regions;
the buried layer is disposed in each space between the trench formed regions without intersecting with the trench formed regions; and
a plurality of the emitter layers is disposed spaced from one another in a direction intersecting with the trench formed regions, the contact layer and the buried layer.
4 . A semiconductor device according to claim 2 , wherein, in plane view of the main surface, a plurality of the trench formed regions is disposed spaced from one another;
the contact layer is disposed in each space between the trench formed regions without intersecting with the trench formed regions;
the buried layer is disposed in each space between the trench formed regions without intersecting with the trench formed regions; and
a plurality of the emitter layers is disposed spaced from one another in a direction intersecting with the trench formed regions, the contact layer and the buried layer.
5 . A semiconductor device according to claim 1 , wherein, in plane view of the main surface, a plurality of the trench formed regions is disposed spaced from one another;
the buried layer is disposed in each space between the trench formed regions without intersecting with the trench formed regions;
a plurality of the emitter layers is disposed spaced from one another in a direction intersecting with the trench formed regions and the buried layer; and
the contact layer is disposed in each space between the trench formed regions and between the emitter layers.
6 . A semiconductor device according to claim 2 , wherein, in plane view of the main surface, a plurality of the trench formed regions is disposed spaced from one another;
the buried layer is disposed in each space between the trench formed regions without intersecting with the trench formed regions;
a plurality of the emitter layers is disposed spaced from one another in a direction intersecting with the trench formed regions and the buried layer; and
the contact layer is disposed in each space between the trench formed regions and between the emitter layers.
7 . A semiconductor device including an insulated gate bipolar transistor, comprising:
a base layer of a first conductivity type impurity region;
a trench formed region formed within the base layer;
a gate insulating film and a gate electrode formed within the trench formed region;
a body layer of a second conductivity type impurity region formed in contact with the trench formed region within the base layer;
an emitter layer of the first conductivity type impurity region formed on a main surface of the body layer;
a contact layer of the second conductivity impurity region formed on the main surface of the body layer in a state that the contact layer is thinner in thickness than the emitter layer, and has a surface concentration smaller than the emitter layer; and
a buried layer of the second conductivity type impurity region formed spaced from the trench formed region in the body layer, and an impurity concentration peak position of the buried layer is deeper than an impurity concentration peak position of the contact layer.
8 . A semiconductor device according to claim 7 , wherein the buried layer is provided in a state that a breakdown voltage of a PN junction composed of the body layer wherein the buried layer is formed and the base layer is lower than a breakdown voltage between a bottom corner of the trench formed region formed within the base layer and the base layer.
9 . A semiconductor device according to claim 7 , wherein, in plane view of the main surface, a plurality of the trench formed regions is disposed spaced from one another;
the buried layer is disposed in each space between the trench formed regions without intersecting with the trench formed regions;
a plurality of the emitter layers is disposed spaced from one another in a direction intersecting with the trench formed regions and the buried layer; and
the contact layer is disposed in a region surrounded by the trench formed regions and the emitter layers, and in a region including a portion of the emitter layer or the entire emitter layer.
10 . A semiconductor device according to claim 8 , wherein, in plane view of the main surface, a plurality of the trench formed regions is disposed spaced from one another;
the buried layer is disposed in each space between the trench formed regions without intersecting with the trench formed regions;
a plurality of the emitter layers is disposed spaced from one another in a direction intersecting with the trench formed regions and the buried layer; and
the contact layer is disposed in a region surrounded by the trench formed regions and the emitter layers, and in a region including a portion of the emitter layer or the entire emitter layer.
11 . A semiconductor device according to claim 1 , further comprising:
a collector layer of the second conductivity type impurity region formed on opposite side of the body layer.
12 . A semiconductor device according to claim 2 , further comprising:
a collector layer of the second conductivity type impurity region formed on opposite side of the body layer.
13 . A semiconductor device according to claim 7 , further comprising:
a collector layer of the second conductivity type impurity region formed on opposite side of the body layer.
14 . A semiconductor device according to claim 8 , further comprising:
a collector layer of the second conductivity type impurity region formed on opposite side of the body layer.
15 . A semiconductor device according to claim 1 , further comprising:
an element isolation film formed adjacent to the base layer on opposite side of the body layer in the depth direction; and
a collector layer of the second conductivity type impurity region formed apart from the body layer on the same side of the body layer.
16 . A semiconductor device according to claim 2 , further comprising:
an element isolation film formed adjacent to the base layer on opposite side of the body layer in the depth direction; and
a collector layer of the second conductivity type impurity region formed apart from the body layer on the same side of the body layer.
17 . A semiconductor device according to claim 7 , further comprising:
an element isolation film formed adjacent to the base layer on opposite side of the body layer in the depth direction; and
a collector layer of the second conductivity type impurity region formed apart from the body layer on the same side of the body layer.
18 . A semiconductor device according to claim 8 , further comprising:
an element isolation film formed adjacent to the base layer on opposite side of the body layer in the depth direction; and
a collector layer of the second conductivity type impurity region formed apart from the body layer on the same side of the body layer.