FinFET device and method of manufacturing same

• US 8,828,823 B2
• Filed: 04/02/2014
• Issued: 09/09/2014
• Est. Priority Date: 10/13/2011
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Liu, Chi-Wen, Wang, Chao-Hsiung
• Primary Examiner(s): Such, Matthew W
• Assistant Examiner(s): Harrison, Monica D
• Application Number:
  US14/243,457
• Publication Number:
  US 20140206166A1
• Time in Patent Office: 160 Days
• Field of Search: 438/283, 257/288, 257/E29.242, 257/E21.409
• US Class Current: 438/283
• CPC Class Codes: H01L 21/76224 using trench refilling with dielectric materials trench filling with polycristalline silicon H01L21/763; together with vertical isolation, e.g. trench refilling in a SOI substrate H01L21/76264
• CPC Class Codes: H01L 29/66795 with a horizontal current flow in a vertical sidewall of a semiconductor body, e.g. FinFET, MuGFET
• CPC Class Codes: H01L 29/7843 the means being an applied insulating layer
• CPC Class Codes: H01L 29/7845 the means being a conductive material, e.g. silicided S/D or Gate
• CPC Class Codes: H01L 29/785 having a channel with a horizontal current flow in a vertical sidewall of a semiconductor body, e.g. FinFET, MuGFET

Abstract

A semiconductor device and method for fabricating a semiconductor device is disclosed. An exemplary semiconductor device includes a substrate including a fin structure including one or more fins disposed on the substrate. The semiconductor device further includes a dielectric layer disposed on a central portion of the fin structure and traversing each of the one or more fins. The semiconductor device further includes a work function metal disposed on the dielectric layer and traversing each of the one or more fins. The semiconductor device further includes a strained material disposed on the work function metal and interposed between each of the one or more fins. The semiconductor device further includes a signal metal disposed on the work function metal and on the strained material and traversing each of the one or more fins.

Claims

1. A method of forming a semiconductor device comprising:

forming a plurality of fins over a substrate;

forming an insulation material in a region between the plurality of fins;

forming a dielectric layer over the plurality of fins and over the insulation material in the region between the plurality of fins;

forming a work function metal over the plurality of fins and over the dielectric layer in the region between the plurality of fins;

forming a strained material over the work function metal in the region between the plurality of fins; and

forming a signal metal over the plurality of fins, over the work function metal, and over the strained material.

2. The method of claim 1 wherein the strained material has a coefficient of thermal expansion (CTE) that is different than a CTE of the work function metal and a CTE of the signal metal, and

wherein the signal metal separates source and drain regions of the semiconductor device, the source and drain regions defining channel regions of the plurality of fins.

3. The method of claim 2 wherein the strained material induces a compressive stress in a current flow direction of the channel regions.

4. The method of claim 2 wherein the strained material induces a tensile stress in a current flow direction of the channel regions.

5. The method of claim 1 wherein the semiconductor device is one of a P-type metal-oxide-semiconductor (PMOS) fin-like field effect transistor (FinFET) device or a N-type metal-oxide-semiconductor (NMOS) FinFET device, and wherein the semiconductor device is included in an integrated circuit device.

6. The method of claim 1 wherein the strained material is selected from the group consisting of a dielectric material and a metal material.

7. The method of claim 1 wherein the strained material includes titanium silicide (TiSi) and the work function metal includes titanium nitride (TiN).

8. The method of claim 1 wherein the strained material includes polyimide (PI) and the work function metal includes titanium aluminide (TiAl).

9. A method of forming a semiconductor device comprising:

forming first and second fins over a substrate;

depositing a dielectric layer over a central portion of the first and second fins;

depositing a work function metal over the dielectric layer and over the first and second fins;

depositing a strained material over the work function metal and interposed between the first and second fins; and

depositing a signal metal over the work function metal and over the strained material, the signal metal traversing the first and second fins.

10. The method of claim 9 wherein the signal metal separates source and drain regions of the semiconductor device, the source and drain regions defining channel regions of the first and second fins,

wherein the strained material induces a compressive stress in a current flow direction of the channel regions, and

wherein the strained material has a coefficient of thermal expansion (CTE) that is less than a CTE of the work function metal and different than a CTE of the signal metal.

11. The method of claim 10 wherein the semiconductor device is a P-type metal-oxide-semiconductor (PMOS) fin-like field effect transistor (FinFET) device.

12. The method of claim 9 wherein the signal metal separates source and drain regions of the semiconductor device, the source and drain regions defining channel regions of the first and second fins,

wherein the strained material induces a tensile stress in a current flow direction of the channel regions, and

wherein the strained material has a coefficient of thermal expansion (CTE) that is greater than a CTE of the work function metal and different than a CTE of the signal metal.

13. The method of claim 12 wherein the semiconductor device is a N-type metal-oxide-semiconductor (NMOS) fin-like field effect transistor (FinFET) device.

14. A method of manufacturing a semiconductor device, comprising:

providing a substrate;

forming a fin structure including one or more fins over the substrate, each of the one or more fins including first and second sidewalls;

depositing an insulation material on the substrate and the fin structure, the insulation material substantially filling a region between each of the one or more fins;

removing a portion of the insulation material from the region between each of the one or more fins such that a portion of the first and second sidewalls of each of the one or more fins is exposed;

forming a dielectric layer over a central portion of each of the one or more fins;

forming a work function metal over the dielectric layer and disposed in the region between each of the one or more fins;

forming a strained material on the work function metal, the strained material being disposed in the region between each of the one or more fins; and

etching back the strained material in the region between each of the one or more fins.

15. The method of claim 14 further comprising:

forming a signal metal over the work function metal and the etched back strained material, the signal metal traversing each of the one or more fins and separating source and drain regions of the semiconductor device, the source and drain regions defining a channel region, for each of the one or more fins, therebetween; and

forming source and drain features in the source and drain regions,

wherein forming the source and drain features includes recessing a portion of each of the one or more fins and epitaxially (epi) growing a semiconductor material on the recessed portions of each of the one or more fins.

16. The method of claim 14 wherein forming the strained material includes:

a spin-on process; and

a process temperature less than an operating temperature of the semiconductor device.

17. The method of claim 16 wherein forming the strained material includes depositing a metal material having a coefficient of thermal expansion (CTE) less than a CTE of the work function metal.

18. The method of claim 16 wherein forming the strained material includes depositing a dielectric material having a coefficient of thermal expansion (CTE) greater than a CTE of the work function metal.

19. The method of claim 14 wherein forming the strained material includes:

a spin-on process; and

a process temperature greater than an operating temperature of the semiconductor device.

20. The method of claim 19 wherein forming the strained material includes depositing a material having a coefficient of thermal expansion (CTE) less than a CTE of the work function metal and different than a CTE of the signal metal.