METHOD OF FORMING CONTACT STRUCTURE OF GATE STRUCTURE

• US 20150206872A1
• Filed: 01/17/2014
• Published: 07/23/2015
• Est. Priority Date: 01/17/2014
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: HSU, AUDREY HSIAO-CHIU, YANG, FU-KAI, WANG, MEI-YUN, WANG, HSIEN-CHENG, LIU, SHIH-WEN, LIN, HSIN-YING
• Granted Patent: US 9,123,563 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01L 21/2633 for etching, e.g. sputteretching
• CPC Class Codes: H01L 21/28518 the conductive layers comprising silicides H01L21/28537 takes precedence
• CPC Class Codes: H01L 21/31116 by dry-etching
• CPC Class Codes: H01L 21/32051 Deposition of metallic or metal-silicide layers
• CPC Class Codes: H01L 21/32053 of metal-silicide layers
• CPC Class Codes: H01L 21/32105 Oxidation of silicon-containing layers
• CPC Class Codes: H01L 21/3212 by chemical mechanical polishing [CMP]
• CPC Class Codes: H01L 21/76805 the opening being a via or contact hole penetrating the underlying conductor
• CPC Class Codes: H01L 21/76831 in via holes or trenches, e.g. non-conductive sidewall liners
• CPC Class Codes: H01L 21/7684 Smoothing; Planarisation
• CPC Class Codes: H01L 21/76897 Formation of self-aligned vias or contact plugs, i.e. involving a lithographically uncritical step self-aligned silicidation on field effect transistors H01L29/665
• CPC Class Codes: H01L 21/823425 manufacturing common source or drain regions between a plurality of conductor-insulator-semiconductor structures
• CPC Class Codes: H01L 21/823475 interconnection or wiring or contact manufacturing related aspects
• CPC Class Codes: H01L 23/485 consisting of layered constructions comprising conductive layers and insulating layers, e.g. planar contacts H01L23/4821, H01L23/4822, H01L23/4824, H01L23/4825 take precedence; materials H01L23/532, bond pads H01L24/02, bump connectors H01L24/10
• CPC Class Codes: H01L 23/53261 Refractory-metal alloys
• CPC Class Codes: H01L 23/53266 Additional layers associated with refractory-metal layers, e.g. adhesion, barrier, cladding layers
• CPC Class Codes: H01L 23/535 including internal interconnections, e.g. cross-under constructions internal lead connections H01L23/481
• CPC Class Codes: H01L 27/088 the components being field-effect transistors with insulated gate
• CPC Class Codes: H01L 29/4933 with a silicide layer contacting the silicon layer, e.g. Polycide gate with a barrier layer between the silicide and silicon layers H01L29/4941
• CPC Class Codes: H01L 29/665 using self aligned silicidation, i.e. salicide formation of conductive layers comprising silicides H01L21/28518
• CPC Class Codes: H01L 29/66515 : using self aligned selective metal deposition simultaneously on the gate and on source or drain
• CPC Class Codes: H01L 29/6653 : using the removal of at least part of spacer, e.g. disposable spacer
• CPC Class Codes: H01L 29/6656 : using multiple spacer layers, e.g. multiple sidewall spacers
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 : Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

A method of forming a contact structure of a gate structure is provided. In the method, an oxidation layer and a first sidewall layer disposed between a first metal gate and a second metal gate are etched to expose an underlying silicon substrate. A silicide portion defined by a contact profile is deposited in the exposed portion of the silicon substrate. A second sidewall layer substantially covers the first sidewall layer and at least partially covering the silicide portion is formed after depositing the silicide portion. A metal glue layer is deposited around the first metal gate and the second metal gate defining a trench above the silicide portion. A metal plug is deposited within the trench.

Claims

1. A method of forming a contact structure of a gate structure, comprising:

etching an oxidation layer and a first sidewall layer disposed between a first metal gate and a second metal gate to expose an underlying silicon substrate;

depositing a silicide portion defined by a contact profile in the exposed portion of the silicon substrate;

forming a second sidewall layer substantially covering the first sidewall layer and at least partially covering the silicide portion after the depositing the silicide portion;

depositing a metal glue layer around the first metal gate and the second metal gate defining a trench above the silicide portion; and

depositing a metal plug within the trench.

2. The method of claim 1, further comprising:

performing a first chemical-mechanical polishing (CMP) process on the first metal gate, the second metal gate, the first sidewall layer, and the oxidation layer before the etching the oxidation layer and the first sidewall.

3. The method of claim 1, further comprising:

performing a second CMP process on the metal plug, the metal glue layer, the first metal gate, the second metal gate, the first sidewall layer, and the second sidewall layer.

4. The method of claim 1, wherein the etching the oxidation layer and the first sidewall layer to expose the underlying silicon substrate comprises performing an isotropic etching process substantially on the oxidation layer and the first sidewall layer.

5. The method of claim 4, wherein the isotropic etching process is an ion bombardment process.

6. The method of claim 1, further comprising:

forming the first sidewall layer using a material selected from the group consisting of SiN_x, SiO_(1-x)N_x, SiC_(1-x)N_x, SiO_(1-x-y)C_xN_y, Ti_(1-x)Nx, and Al_(1-x)N_x;

wherein the forming the second sidewall layer comprises forming the second sidewall layer using a material selected from the group consisting of SiO_x, SiO_xC_(1-x), SiN_x, SiO_(1-x)N_x, SiC_(1-x)N_x, SiO_(1-x-y)C_xN_y, Ti_(1-x)N_x, and Al_(1-x)N_x; and

wherein the depositing the silicide portion comprises depositing the silicide portion using a material selected from the group consisting of Ti_(1-x)Si_x, Co_(1-x)Si_x, Ni_(1-x)Si_x, Ti_(1-x)Si_xGe, Co_(1-x)Si_xGe, and Ni_(1-x)Si_xGe.

7. A method of forming a contact structure of a gate structure, comprising:

etching an oxidation layer and a first sidewall layer disposed between a first metal gate and a second metal gate to expose an underlying silicon substrate;

depositing a silicide portion defined by a contact profile in the exposed portion of the silicon substrate;

depositing a metal glue layer around the first metal gate and the second metal gate defining a trench above the silicide portion; and

depositing a metal plug within the trench.

8. The method of claim 7, further comprising:

performing a first chemical mechanical polishing (CMP) process on the first metal gate, the second metal gate, the first sidewall layer, and the oxidation layer before the etching the oxidation layer and the first sidewall.

9. The method of claim 7, further comprising:

performing a second CMP process on the metal plug, the metal glue layer, the first metal gate, the second metal gate, and the first sidewall layer.

10. The method of claim 7, further comprising:

forming a second sidewall layer substantially covering the first sidewall layer and at least partially covering the silicide portion after the depositing the silicide portion.

21. The method of claim 10, wherein forming the second sidewall layer further comprises forming the second sidewall layer by using a material selected from the group consisting of SiO_x, SiO_xC_(1-x), SiN_x, SiO_(1-x)N_x, SiC_(1-x)N_x, SiO_(1-x-y)C_xN_y, Ti_(1-x)N_x, and Al_(1-x)N_x.

22. The method of claim 10, wherein forming the second sidewall layer further comprises forming the second sidewall layer with an average thickness between about 10 angstrom (Å

) and about 50 Å

.

23. The method of claim 7, further comprising forming the first sidewall layer by using a nitride-based film.

24. The method of claim 23, further comprising forming the first sidewall layer by using a material selected from the group consisting of SiN_x, SiO_(1-x)N_x, SiC_(1-x)N_x, SiO_(1-x-y)C_xN_y, Ti_(1-x)N_x, and Al_(1-x)N_x.

25. The method of claim 23, wherein forming the first sidewall layer further comprises forming the first sidewall layer with an average thickness between about 1 nanometer (nm) and about 5 nm.

11-20. -20. (canceled)

26. A method of forming a contact structure of a gate structure, comprising:

etching an oxidation layer and a first sidewall layer disposed between a first metal gate and a second metal gate to expose an underlying silicon substrate;

depositing a silicide portion defined by a contact profile in the exposed portion of the silicon substrate;

depositing a metal glue layer around the first metal gate and the second metal gate defining a trench above the silicide portion;

depositing a metal plug within the trench; and

performing a first chemical mechanical polishing (CMP) process on the first metal gate, the second metal gate, the first sidewall layer, and the oxidation layer before the etching the oxidation layer and the first sidewall.

27. The method of claim 26, further comprising:

performing a second CMP process on the metal plug, the metal glue layer, the first metal gate, the second metal gate, and the first sidewall layer.

28. The method of claim 26, further comprising:

forming a second sidewall layer substantially covering the first sidewall layer and at least partially covering the silicide portion after the depositing the silicide portion.

29. The method of claim 28, wherein forming the second sidewall layer further comprises forming the second sidewall layer by using a material selected from the group consisting of SiO_x, SiO_xC_(1-x), SiN_x, SiO_(1-x)N_x, SiC_(1-x)N_x, SiO_(1-x-y)C_xN_y, Ti_(1-x)N_x, and Al_(1-x)N_x.

30. The method of claim 28, wherein forming the second sidewall layer further comprises forming the second sidewall layer with an average thickness between about 10 angstrom (Å

) and about 50 Å

.