# US 11,908,954 B2 · Semiconductor device with insulated gate bipolar transistor region and diode region provided on semiconductor substrate and adjacent to each other

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,908,954 B2
- Document ID: US11908954B2
- Status: Granted
- Kind: B2
- Application number: 17/029,162
- Filed: 2020-09-23
- Published: 2021-09-30
- Granted: 2024-02-20
- Earliest claimed: 2020-03-26
- Assignees: Mitsubishi Electric Corporation
- Applicants: Mitsubishi Electric Corporation
- Inventors: Takahiro Nakatani; Tetsuya Nitta; Kakeru Otsuka
- Web page: https://patentgrep.com/patent/US11908954B2

## CPC

- H10D 8/422: {PN diodes having the PN junctions in mesas}
- H10D 12/038: {having a recessed gate, e.g. trench-gate IGBTs}
- H10D 12/481: {having gate structures on slanted surfaces, on vertical surfaces, or in grooves, e.g. trench gate IGBTs}
- H10D 62/109: {Reduced surface field [RESURF] PN junction structures}
- H10D 62/127: {of cellular field-effect devices, e.g. multicellular DMOS transistors or IGBTs}
- H10D 62/142: {Anode regions of thyristors or collector regions of gated bipolar-mode devices}
- H10D 62/393: {Body regions of DMOS transistors or IGBTs (cell layout of DMOS H10D62/127)}
- H10D 64/117: {Recessed field plates, e.g. trench field plates or buried field plates}
- H10D 84/121: {BJTs having built-in components}
- H10D 84/143: {the built-in components being PN junction diodes}
- H10D 84/161: {IGBT having built-in components}
- H10D 84/811: {Combinations of field-effect devices and one or more diodes, capacitors or resistors}
- H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES

## Abstract

A semiconductor device includes an insulated gate bipolar transistor region and a diode region adjacent to each other, wherein the insulated gate bipolar transistor region includes base layers of a second conductive type provided on the first main surface side, emitter layers of the first conductive type selectively provided in a surface layer of the base layer on the first main surface side, multiple gate electrodes provided on the first main surface side of the semiconductor substrate, aligned in a first direction extending along the first main surface, and facing the emitter layer, the base layer, and the drift layer via a gate insulating film, carrier injection suppression layers of the first conductive type selectively provided in a surface layer of the base layer on the first main surface side and sandwiched by the base layers in the first direction.

## Claims

### Claim 1

A semiconductor device comprising:
a semiconductor substrate having a drift layer of a first conductive type between a first main surface and a second main surface opposite to the first main surface; and
an insulated gate bipolar transistor region and a diode region provided on the semiconductor substrate and adjacent to each other, wherein
the insulated gate bipolar transistor region includes
base layers of a second conductive type provided in a surface layer of the semiconductor substrate on a first main surface side,
emitter layers of the first conductive type selectively provided in a surface layer of the base layer on the first main surface side,
multiple gate electrodes provided on the first main surface side of the semiconductor substrate, aligned in a first direction extending along the first main surface, and facing the emitter layer, the base layer, and the drift layer via a gate insulating film,
carrier injection suppression layers of the first conductive type selectively provided in the surface layer of the base layer on the first main surface side and sandwiched by the base layers in the first direction between a first pair of the gate electrodes adjacent to each other in the first direction, each carrier injection suppression layer having a respective bottom surface that is opposite to the first main surface of the semiconductor substrate, and the respective bottom surface of each carrier injection suppression layer is in direct contact with one of the base layers, and
a collector layer of the second conductive type provided in a surface layer of the semiconductor substrate on the second main surface side,
the diode region includes
an anode layer of the second conductive type provided in the surface layer of the semiconductor substrate on the first main surface side, and
a cathode layer of the first conductive type provided in a second surface layer of the semiconductor substrate on the second main surface side,
the insulated gate bipolar transistor region further includes
a second pair of the gate electrodes adjacent to one another,
a first region between the first pair of adjacent gate electrodes and including the carrier injection suppression layers,
a second region between the second pair of gate electrodes and including plural of the base and emitter layers but no carrier injection suppression layer, and
the first region is located closer to the diode region than the second region.

### Claim 2 (depends on 1)

The semiconductor device according to claim 1, wherein
the carrier injection suppression layers are each sandwiched by two of the emitter layers in a second direction orthogonal to the first direction and extending along the first main surface.

### Claim 3 (depends on 1)

The semiconductor device according to claim 1, wherein
the emitter layers are each in contact with one of the carrier injection suppression layers in a second direction orthogonal to the first direction and extending along the first main surface.

### Claim 4 (depends on 1)

The semiconductor device according to claim 1, wherein
the carrier injection suppression layers and the emitter layers longitudinally extend in a longitudinal direction and laterally extend in a lateral direction orthogonal to the longitudinal direction in a plan view, and
a width of the carrier injection suppression layers in the lateral direction is less than a width of the emitter layers in the lateral direction.

### Claim 5 (depends on 1)

The semiconductor device according to claim 1, wherein
the emitter layers and the carrier injection suppression layers have same first conductivity type impurities.

### Claim 6 (depends on 1)

The semiconductor device according to claim 1, wherein
the base layers include a high-concentration base layer on the first main surface side, and a low-concentration base layer having a lower concentration than the high-concentration base layer and provided on the second main surface side of the high-concentration base layer.

### Claim 7 (depends on 1)

The semiconductor device according to claim 1, wherein
the anode layer includes a high-concentration anode layer on the first main surface side, and a low-concentration anode layer having a lower concentration than the high-concentration anode layer and provided on the second main surface side of the high-concentration anode layer.

### Claim 8 (depends on 1)

The semiconductor device according to claim 1, wherein
an impurity concentration of the carrier injection suppression layers and an impurity concentration of the emitter layers is each greater than or equal to 1E17 cm−3 and less than or equal to 1E20 cm−3.

### Claim 9 (depends on 1)

The semiconductor device according to claim 1, wherein
no carrier injection suppression layers are formed in the diode area.

### Claim 10

A semiconductor device comprising:
a semiconductor substrate having a drift layer of a first conductive type between a first main surface and a second main surface opposite to the first main surface; and
an insulated gate bipolar transistor region and a diode region provided on the semiconductor substrate and adjacent to each other, wherein
the insulated gate bipolar transistor region includes
base layers of a second conductive type provided in a surface layer of the semiconductor substrate on a first main surface side,
emitter layers of the first conductive type selectively provided in a surface layer of the base layer on the first main surface side,
multiple gate electrodes provided on the first main surface side of the semiconductor substrate, aligned in a first direction extending along the first main surface, and facing the emitter layer, the base layer, and the drift layer via a gate insulating film,
carrier injection suppression layers of the first conductive type selectively provided in the surface layer of the base layer on the first main surface side and sandwiched by the base layers in the first direction between a first pair of the gate electrodes adjacent to each other in the first direction, each carrier injection suppression layer having a respective bottom surface that is opposite to the first main surface of the semiconductor substrate, and the respective bottom surface of each carrier injection suppression layer is in direct contact with one of the base layers, and
a collector layer of the second conductive type provided in a surface layer of the semiconductor substrate on the second main surface side,
the diode region includes
an anode layer of the second conductive type provided in the surface layer of the semiconductor substrate on the first main surface side, and
a cathode layer of the first conductive type provided in a second surface layer of the semiconductor substrate on the second main surface side, and
the insulated gate bipolar transistor region further includes
a second pair of the gate electrodes adjacent to one another,
a first region between the first pair of adjacent gate electrodes and including the carrier injection suppression layers, the first region being adjacent to the diode region in the first direction, and
a second region between the second pair of gate electrodes and including plural of the base and emitter layers, the second region being separated from the diode region in the first direction and including no carrier injection suppression.
