SEMICONDUCTOR DEVICE, INVERTER CIRCUIT, DRIVE DEVICE, VEHICLE, AND ELEVATOR

Abstract

A semiconductor device of embodiments includes: a silicon carbide layer having a first face parallel to a first direction and a second direction crossing the first direction and a second face facing the first face; a first trench on a side of the first face extending in the first direction; a second trench extending in the first direction; a third trench extending in the second direction and continuous with the first trench and the second trench; a fourth trench extending in the first direction, disposed between the first trench and the second trench, and spaced from the third trench in the first direction; a gate electrode in the first to fourth trench; a gate insulating layer; a first conductive layer crossing the third trench and connected to the gate electrode; a first electrode disposed on the first face; and a second electrode disposed on the second face.

Description

Claims

1. A semiconductor device, comprising: a silicon carbide layer having a first face parallel to a first direction and a second direction crossing the first direction and a second face facing the first face;a first trench disposed in the silicon carbide layer, disposed on a side of the first face, and extending in the first direction;a second trench disposed in the silicon carbide layer, disposed on the side of the first face, extending in the first direction, and disposed in the second direction with respect to the first trench;a third trench disposed in the silicon carbide layer, disposed on the side of the first face, extending in the second direction, and continuous with the first trench and the second trench;a fourth trench disposed in the silicon carbide layer, disposed on the side of the first face, extending in the first direction, disposed between the first trench and the second trench, and spaced from the third trench in the first direction;a first silicon carbide region of n-type disposed in the silicon carbide layer;a second silicon carbide region of p-type disposed in the silicon carbide layer and disposed between the first silicon carbide region and the first face, a distance of the second silicon carbide region from the second face being larger than a distance from the second face to the first trench;a third silicon carbide region of n-type disposed in the silicon carbide layer and disposed between the second silicon carbide region and the first face;a gate electrode disposed in the first trench, the second trench, the third trench, and the fourth trench;a gate insulating layer disposed between the gate electrode and the silicon carbide layer;a first wiring layer disposed on the side of the first face with respect to the silicon carbide layer, disposed in the first direction with respect to the third trench, and extending in the second direction;a first conductive layer crossing the third trench, connected to the gate electrode, and is electrically connected to the first wiring layer;a first electrode disposed on the side of the first face with respect to the silicon carbide layer and electrically connected to the third silicon carbide region; anda second electrode disposed on a side of the second face with respect to the silicon carbide layer.

2. The semiconductor device according to claim 1, wherein the gate electrode and the first conductive layer contain a same material.

3. The semiconductor device according to claim 2, wherein the same material is polycrystalline silicon.

4. The semiconductor device according to claim 1, wherein the gate insulating layer is disposed between the first conductive layer and the silicon carbide layer.

5. The semiconductor device according to claim 1, wherein a shape of the third trench crossing the first conductive layer on the first face is a linear shape.

6. The semiconductor device according to claim 1, wherein a side surface of the third trench crossing the first conductive layer is formed by an a-face or an m-face.

7. The semiconductor device according to claim 1, wherein a sum of a width of the first trench in the second direction and a distance between the first trench and the fourth trench in the second direction is equal to or less than 2 µm.

8. The semiconductor device according to claim 1, further comprising: a fifth trench disposed in the silicon carbide layer, disposed on the side of the first face, extending in the first direction, disposed between the fourth trench and the second trench, and spaced from the third trench in the first direction; anda sixth trench disposed in the silicon carbide layer, disposed on the side of the first face, extending in the second direction, continuous with the fourth trench and the fifth trench, and spaced from the third trench in the first direction.

9. The semiconductor device according to claim 1, further comprising: a seventh trench disposed in the silicon carbide layer, disposed on the side of the first face, and extending in the first direction, the first trench being disposed between the fourth trench and the seventh trench; andan eighth trench disposed in the silicon carbide layer, disposed on the side of the first face, extending in the second direction, continuous with the fourth trench and the seventh trench, and spaced from the first trench in the first direction.

10. The semiconductor device according to claim 9, further comprising: a second wiring layer disposed on the side of the first face with respect to the silicon carbide layer, disposed in the first direction with respect to the eighth trench, and extending in the second direction; anda second conductive layer crossing the eighth trench, connected to the gate electrode, and electrically connected to the second wiring layer.

11. An inverter circuit, comprising: the semiconductor device according to claim 1.

12. A drive device, comprising: the semiconductor device according to claim 1.

13. A vehicle, comprising: the semiconductor device according to claim 1.

14. An elevator, comprising: the semiconductor device according to claim 1.