Semiconductor device and method for forming the same

Abstract

A semiconductor device includes: an epitaxial layer on a substrate; a plurality of transistor elements in the epitaxial layer; a source electrode on the epitaxial layer; a Schottky metal between the transistor elements and in contact with the epitaxial layer, wherein the Schottky metal has a T-shaped profile; and a source electrode covering the Schottky metal and electrically connected to the transistor elements.

Claims

1. A semiconductor device comprising: an epitaxial layer on a substrate; a plurality of transistor elements in the epitaxial layer; a Schottky metal between the transistor elements and in contact with the epitaxial layer, wherein the Schottky metal has a T-shaped profile, wherein the Schottky metal has an upper portion extending along an upper surface of the epitaxial layer and a lower portion extending into the epitaxial layer; and a source electrode covering the Schottky metal and electrically connected to the transistor elements.

2. The semiconductor device as claimed in claim 1, wherein the epitaxial layer has a doped region located on a bottom surface of the lower portion of the Schottky metal.

3. The semiconductor device of claim 1, wherein each of the transistor elements comprises: a well region having a first conductivity type; a first doped region located above the well region and having the first conductivity type; a second doped region located above the well region and adjacent to the first doped region, and having a second conductivity type different from the first conductivity type; and a gate structure wherein one side surface of the gate structure contacts the well region and the second doped region, wherein the Schottky metal is separated from the first doped region of each of the transistor elements.

4. The semiconductor element as claimed in claim 3, wherein the Schottky metal is separated from the second doped region of each of the transistor elements.

5. The semiconductor element as claimed in claim 1, wherein the T-shaped profile of the Schottky metal is mirror symmetrical.

6. A method for forming a semiconductor element, comprising: forming an epitaxial layer on a substrate; forming a plurality of transistor elements in the epitaxial layer; forming an opening in the epitaxial layer between the transistor elements; depositing a conductive material to fill the opening, and performing a patterning process on the conductive material to form a Schottky metal having a T-shaped profile, wherein the Schottky metal has an upper portion extending along an upper surface of the epitaxial layer and a lower portion extending into the epitaxial layer; and forming a source electrode on the epitaxial layer and covering the Schottky metal.

7. The method of claim 6, further comprising forming a doped region in the epitaxial layer via the opening prior to depositing the conductive material.

8. The method of claim 6, wherein each of the transistor elements comprises: forming a well region in the epitaxial layer, wherein the well region has a first conductivity type; forming a first doped region above the well region, wherein the first doped region has the first conductivity type; forming a second doped region above the well region, wherein the second doped region is adjacent to the first doped region and wherein the second doped region has a second conductivity type different from the first conductivity type, wherein the opening is separated from the first doped region and the second doped region; and forming a gate structure in the epitaxial layer, wherein one side surface of the gate structure contacts the well region and the second doped region.

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