Semiconductor device
View Patent ↗A semiconductor substrate comprises an IGBT region and a diode region. The IGBT region comprises: an n-type emitter region; a p-type IGBT body region; an n-type IGBT barrier region; an n-type IGBT drift region; a p-type collector region; a first trench; a first insulating layer; and a first gate electrode. The diode region comprises: a p-type diode top body region; an n-type diode barrier region; a p-type diode bottom body region; an n-type cathode region; a second trench; a second insulating layer; and a second gate electrode. An n-type impurity density of a specific part of the diode barrier region making contact with the second insulating layer is higher than an n-type impurity density of the IGBT barrier region.
1. A semiconductor device comprising a semiconductor substrate, wherein the semiconductor substrate comprises an IGBT region and a diode region,
the IGBT region comprises:
an n-type emitter region exposed at a part of a front surface of the semiconductor substrate;
a p-type IGBT body region formed at a deeper position than the emitter region;
an n-type IGBT barrier region formed at a deeper position than the IGBT body region;
an n-type IGBT drift region formed at a deeper position than the IGBT barrier region, having an n-type impurity density lower than that in the IGBT barrier region;
a p-type collector region formed at a deeper position than the IGBT drift region, wherein the collector region is exposed at a rear surface of the semiconductor substrate;
a first trench penetrating the emitter region, the IGBT body region and the IGBT barrier region, wherein a bottom part of the first trench projects into the IGBT drift region;
a first insulating layer covering an inner surface of the first trench; and
a first gate electrode contained in the first trench in a state where the first gate electrode is covered by the first insulating layer,
the diode region comprises:
a p-type diode top body region exposed at the front surface of the semiconductor substrate;
an n-type diode barrier region formed at a deeper position than the diode top body region;
a p-type diode bottom body region formed at a deeper position than the diode barrier region;
an n-type cathode region formed at a deeper position than the diode bottom body region, wherein the cathode region is exposed at the rear surface of the semiconductor substrate;
a second trench penetrating the diode top body region, the diode barrier region and the diode bottom body region, wherein a bottom part of the second trench projects into the cathode region;
a second insulating layer covering an inner surface of the second trench; and
a second gate electrode contained in the second trench in a state where the second gate electrode is covered by the second insulating layer, and
an n-type impurity density of a specific part of the diode barrier region making contact with the second insulating layer is higher than an n-type impurity density of the IGBT barrier region.
2. The semiconductor device as in claim 1 , wherein
the n-type impurity density of the specific part is higher than an n-type impurity density of a part other than the specific part of the diode barrier region.
3. A semiconductor device comprising a semiconductor substrate, wherein the semiconductor substrate comprises an IGBT region and a diode region,
the IGBT region comprises:
an n-type emitter region exposed at a part of a front surface of the semiconductor substrate;
a p-type IGBT body region formed at a deeper position than the emitter region;
an n-type IGBT barrier region formed at a deeper position than the IGBT body region;
an n-type IGBT drift region formed at a deeper position than the IGBT barrier region, having an n-type impurity density lower than that in the IGBT barrier region;
a p-type collector region formed at a deeper position than the IGBT drift region, wherein the collector region is exposed at a rear surface of the semiconductor substrate;
a first trench penetrating the emitter region, the IGBT body region and the IGBT barrier region, wherein a bottom part of the first trench projects into the IGBT drift region;
a first insulating layer covering an inner surface of the first trench; and
a first gate electrode contained in the first trench in a state where the first gate electrode is covered by the first insulating layer,
the diode region comprises:
a p-type diode top body region exposed at the front surface of the semiconductor substrate;
an n-type diode barrier region formed at a deeper position than the diode top body region;
a p-type diode bottom body region formed at a deeper position than the diode barrier region;
an n-type cathode region formed at a deeper position than the diode bottom body region, wherein the cathode region is exposed at the rear surface of the semiconductor substrate;
a second trench penetrating the diode top body region, the diode barrier region and the diode bottom body region, wherein a bottom part of the second trench projects into the cathode region;
a second insulating layer covering an inner surface of the second trench; and
a second gate electrode contained in the second trench in a state where the second gate electrode is covered by the second insulating layer, and
the second insulating layer is thicker than the first insulating layer.
4. A semiconductor device comprising a semiconductor substrate, wherein the semiconductor substrate comprises an IGBT region and a diode region,
the IGBT region comprises:
an n-type emitter region exposed at a part of a front surface of the semiconductor substrate;
a p-type IGBT body region formed at a deeper position than the emitter region;
an n-type IGBT barrier region formed at a deeper position than the IGBT body region;
an n-type IGBT drift region formed at a deeper position than the IGBT barrier region, having an n-type impurity density lower than that in the IGBT barrier region;
a p-type collector region formed at a deeper position than the IGBT drift region, wherein the collector region is exposed at a rear surface of the semiconductor substrate;
a first trench penetrating the emitter region, the IGBT body region and the IGBT barrier region, wherein a bottom part of the first trench projects into the IGBT drift region;
a first insulating layer covering an inner surface of the first trench; and
a first gate electrode contained in the first trench in a state where the first gate electrode is covered by the first insulating layer,
the diode region comprises:
a p-type diode top body region exposed at the front surface of the semiconductor substrate;
an n-type diode barrier region formed at a deeper position than the diode top body region;
a p-type diode bottom body region formed at a deeper position than the diode barrier region;
an n-type cathode region formed at a deeper position than the diode bottom body region, wherein the cathode region is exposed at the rear surface of the semiconductor substrate;
a second trench penetrating the diode top body region, the diode barrier region and the diode bottom body region, wherein a bottom part of the second trench projects into the cathode region;
a second insulating layer covering an inner surface of the second trench; and
a second gate electrode contained in the second trench in a state where the second gate electrode is covered by the second insulating layer, and
a resistance of a channel formed in the diode bather region is higher than a resistance of a channel formed in the IGBT bather region.