Semiconductor device having diode and IGBT

• US 20090072339A1
• Filed: 08/12/2008
• Published: 03/19/2009
• Est. Priority Date: 09/18/2007
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Kouno, Kenji, Tsuzuki, Yukio
• Granted Patent: US 7,728,382 B2
• Time in Patent Office: Days
• US Class Current: 257/477
• CPC Class Codes: H01L 27/0676 comprising combinations of diodes, or capacitors or resistors
• CPC Class Codes: H01L 29/0623 Buried supplementary region, e.g. buried guard ring multi-RESURF H01L29/0634
• CPC Class Codes: H01L 29/7395 Vertical transistors, e.g. vertical IGBT
• CPC Class Codes: H01L 29/872 Schottky diodes

Abstract

A semiconductor device includes: a semiconductor substrate including a first conductive type layer; a plurality of IGBT regions, each of which provides an IGBT element; and a plurality of diode regions, each of which provides a diode element. The plurality of IGBT regions and the plurality of diode regions are alternately arranged in the substrate. Each diode region includes a Schottky contact region having a second conductive type. The Schottky contact region is configured to retrieve a minority carrier from the first conductive type layer. The Schottky contact region is disposed in a first surface portion of the first conductive type layer, and adjacent to the IGBT region.

Claims

1. A semiconductor device comprising:

a semiconductor substrate including a first conductive type layer;

a plurality of IGBT regions, each of which provides an IGBT element; and

a plurality of diode regions, each of which provides a diode element,

wherein the plurality of IGBT regions and the plurality of diode regions are alternately arranged in the substrate,

wherein each diode region includes a Schottky contact region having a second conductive type,

wherein the Schottky contact region is configured to retrieve a minority carrier from the first conductive type layer, and

wherein the Schottky contact region is disposed in a first surface portion of the first conductive type layer, and adjacent to the IGBT region.

2. The device according to claim 1,

wherein each diode region further includes a trench, which surrounds the Schottky contact region, and

wherein the trench has a rectangular shape, penetrates the Shottky contact region and reaches the first conductive type layer.

3. The device according to claim 1,

wherein each diode region further includes a plurality of ohmic contact regions having the second conductive type,

wherein the plurality of ohmic contact regions is arranged in a dot matrix,

wherein the plurality of ohmic contact regions is disposed in a second surface portion of the first conductive type layer, and

wherein the plurality of ohmic contact regions is disposed on an inside of the diode region from the Schottky contact region.

4. The device according to claim 1,

wherein each diode region further includes a second conductive type region and an ohmic contact region having the second conductive type,

wherein the second conductive type region is disposed in a third surface portion of the first conductive type layer,

wherein the second conductive type region is disposed on an inside of the diode region from the Schottky contact region,

wherein the ohmic contact regions is disposed in a fourth surface portion of the second conductive type region, and

wherein the ohmic contact regions has an impurity concentration higher than the second conductive type region.

5. The device according to claim 4,

wherein each diode region further includes a trench, which surrounds the second conductive type region, and

wherein the trench has a rectangular shape, penetrates the second conductive type region and reaches the first conductive type layer.

6. The device according to claim 5,

wherein the plurality of IGBT regions and the plurality of diode regions are alternately arranged in a repeat direction, and

wherein the ohmic contact region extends along with a direction perpendicular to the repeat direction so that the ohmic contact region has a stripe pattern.

7. The device according to claim 6,

wherein the ohmic contact regions is disposed in a fifth surface portion of the Schottky contact region, and

wherein the ohmic contact region in the Schottky contact region is disposed on an inside of the diode region.

8. The device according to claim 6,

wherein each IGBT region includes:

a second conductive type layer disposed in a sixth surface portion of the first conductive type layer;

a plurality of trenches surrounding the second conductive type layer, having a rectangular shape, penetrating the second conductive type layer and reaching the first conductive type layer, and arranged along with the repeat direction;

a device region disposed between two adjacent trenches, and provided by at least the second conductive type layer; and

a contact portion disposed between two adjacent trenches,

wherein each trench extends along with the direction perpendicular to the repeat direction,

wherein the contact portion extends along with the direction perpendicular to the repeat direction,

wherein the device region extends along with the direction perpendicular to the repeat direction so that the device region has one end and the other end in the direction, and

wherein the Schottky contact region and the second conductive type region are disposed between the one end and the other end of the device region.

9. The device according to claim 8,

wherein the device region includes a groove having a depth shallower than the trench, and

wherein the groove is disposed between two adjacent trenches.

10. The device according to claim 6,

wherein each IGBT region includes:

a second conductive type layer disposed in a seventh surface portion of the first conductive type layer;

a plurality of trenches surrounding the second conductive type layer, having a rectangular shape, penetrating the second conductive type layer and reaching the first conductive type layer, and arranged along with the repeat direction;

a device region disposed between two adjacent trenches, and provided by at least the second conductive type layer; and

a contact portion disposed between two adjacent trenches,

wherein each trench extends along with the direction perpendicular to the repeat direction,

wherein the contact portion extends along with the direction perpendicular to the repeat direction,

wherein the contact portion extends along with the direction perpendicular to the repeat direction so that the contact portion has one end and the other end in the direction,

wherein the Schottky contact region is disposed between the one end and the other end of the contact portion,

wherein the device region extends along with the direction perpendicular to the repeat direction so that the device region has one end and the other end in the direction, and

wherein the second conductive type region is disposed between the one end and the other end of the device region.

11. The device according to claim 10,

wherein the device region includes a groove having a depth shallower than the trench, and

wherein the groove is disposed between two adjacent trenches.

12. A semiconductor device comprising:

a semiconductor substrate including a silicon substrate and a first conductive type layer, wherein the first conductive type layer is disposed on the silicon substrate;

a plurality of IGBT regions, each of which provides an IGBT element; and

a plurality of diode regions, each of which provides a diode element,

wherein the plurality of IGBT regions and the plurality of diode regions are alternately arranged in the semiconductor substrate,

wherein each diode region includes a Schottky contact region having a second conductive type,

wherein the Schottky contact region is configured to retrieve a minority carrier from the first conductive type layer,

wherein the Schottky contact region is disposed in a first surface portion of the first conductive type layer, and adjacent to the IGBT region,

wherein each diode region further includes a second conductive type region and an ohmic contact region having the second conductive type,

wherein the second conductive type region is disposed in a third surface portion of the first conductive type layer,

wherein the second conductive type region is disposed on an inside of the diode region from the Schottky contact region,

wherein the ohmic contact regions is disposed in a fourth surface portion of the second conductive type region,

wherein the ohmic contact regions has an impurity concentration higher than the second conductive type region,

wherein each diode region further includes a trench, which surrounds the second conductive type region and the Schottky contact region, and

wherein the trench has a rectangular shape, penetrates the second conductive type region and the Schottky contact region, and reaches the first conductive type layer.