Semiconductor device and manufacturing method thereof

Patent metadata

Field	Value
Publication number	US-9466678-B2
Application number	US-201514613343-A
Country	US
Kind code	B2
Filing date	Feb 3, 2015
Priority date	Dec 18, 2014
Publication date	Oct 11, 2016
Grant date	Oct 11, 2016

Abstract

The present invention relates to a semiconductor device and a manufacturing method thereof. The semiconductor device includes a substrate, an epitaxial structure, and a recess. The epitaxial structure is disposed in the substrate. The recess is formed in the epitaxial structure, where the recess has a cross-section in a direction perpendicular to the substrate, and at least one portion of the recess is gradually expanded from an opening of the recess.

First claim

What is claimed is:

1. A manufacturing method of a semiconductor device, comprising:
forming a first recess in a substrate;
forming an epitaxial structure in the first recess;
forming a dielectric layer on the substrate;
forming a contact opening in the dielectric layer;
forming a second recess in the epitaxial structure through the contact opening, wherein the second recess has a depth being 30% -70% of a height of the epitaxial structure and has a cross-section along a direction perpendicular to the substrate and at least a portion of the cross-section is gradually expanded from an opening of the second recess; and
performing a silicidation process to form a silicide layer on a surface of the second recess.

2. The manufacturing method of the semiconductor device of claim 1 , wherein the forming of the second recess comprises:
vertically etching the epitaxial structure to form a third recess; and
laterally etching a sidewall of the third recess to form the second recess.

3. The manufacturing method of the semiconductor device of claim 1 , further comprising:
providing a fin-shaped structure, the fin-shaped structure being formed in the substrate and the first recess being formed in the fin-shaped structure.

4. A semiconductor device, comprising:
a substrate;
an epitaxial structure disposed in the substrate;
a recess disposed in the epitaxial structure, wherein the recess has a depth being 30%-70% of a height of the epitaxial structure and has a cross-section along a direction perpendicular to the substrate and at least a portion of the cross-section is gradually expanded from an opening of the recess; and
a contact plug disposed on the substrate, wherein a portion of the contact plug is encompassed by the epitaxial structure.

5. The semiconductor device of claim 4 , wherein the cross-section of the recess has a bottom surface lower than a top surface of the substrate.

6. The semiconductor device of claim 5 , wherein the cross-section of recess has a sidewall, and there is an angle between the sidewall and the top surface of the substrate being between 50 degrees and 72 degrees.

7. The semiconductor device of claim 4 , wherein the cross-section of the recess has a bottom surface, and a lowest portion of the bottom surface is lower than a widest portion a cross-section of the epitaxial structure.

8. The semiconductor device of claim 7 , wherein the bottom surface is an arc bottom surface.

9. The semiconductor device of claim 4 , wherein the cross-section of the recess has a trapezoid shape or a hexagon shape.

10. The semiconductor device of claim 4 , further comprising:
a silicide layer disposed on a surface of the recess.

11. The semiconductor device of claim 10 , further comprising:
a dielectric layer disposed on the substrate; and
the contact plug disposed in the dielectric layer and electrically connected the epitaxial structure.

12. The semiconductor device of claim 11 , wherein the silicide layer is disposed between the contact plug and the epitaxial structure.

13. The semiconductor device of claim 10 , wherein the silicide layer comprises titanium silicide.

14. The semiconductor device of claim 4 , further comprising:
a fin-shaped structure, wherein the epitaxial structure is disposed in the fin-shaped structure.

15. A semiconductor device, comprising:
a substrate;
an epitaxial structure disposed in the substrate;
a recess disposed in the epitaxial structure, wherein the recess has a trapezoid shape and has a depth being 30-70% of a height of the epitaxial structure; and
a contact plug disposed on the substrate, wherein a portion of the contact plug is encompassed by the epitaxial structure.

16. The semiconductor device of claim 15 , further comprising:
a silicide layer disposed on a surface of the recess.

17. The semiconductor device of claim 15 , wherein a cross-section of the recess has a bottom surface, and a lowest portion of the bottom surface is lower than a widest portion a cross-section of the epitaxial structure.

Assignees

• United Microelectronics Corp

Inventors

• Huang Shih-Hsien
• Chang Che-Wei
• Yeh Chih-Chieh
• Tsai Tzu-I

Classifications

• H10P50/00

  Etching of wafers, substrates or parts of devices · CPC title

• H10D64/0112

  using conductive layers comprising silicides · CPC title

• H10W20/047

  by introducing additional elements therein · CPC title

• H10W20/033

  in openings in dielectrics · CPC title

• H10W20/089

  using processes for implementing desired shapes or dispositions of the openings, e.g. double patterning · CPC title