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US5055423A Expired / Lapsed US ⏱️ 0.0 years remaining

Planarized selective tungsten metallization system

Assignee: Texas Instruments Inc
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Filing: 1989-07-18
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Granted: 1991-10-08
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Expires: 2009-07-18
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Abstract

Abstract In an improved selection tungsten metallization system, a plurality of orifices (20) are cut into a first level dielectric layer (18). A nucleation layer (52), preferably Ti-W alloy, is then formed in each orifice (20) and on the outer surface of the first dielectric layer (18) in a second-level metallization pattern. A second dielectric layer (30) is deposited over the first dielectric layer (18) and the nucleation layer (52), and a reverse second level metallization pattern is used to etch slots (58) back down to the nucleation layers (52) and into orifices (20). Thereafter, tungsten is deposited by selective CVD to fill the first level orifices (20) and the second level slots (58) until the upper surfaces (62) of the tungsten conductors (60) are substantially coplanar with the upper surface (38) of the second dielectric layer (30).

Inventors

  • 👤 Gregory C. Smith
  • 👤 Thomas D. Bonifield

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 14:23
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/056; H10W20/057; H10W20/032; H10W20/042; H10W20/045; H10W20/071; H10W20/081; H10W20/084; H10W20/086; H10W20/0886

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 114 words
A process for forming a conductive interconnection in an integrated circuit structure, comprising the steps of: providing a partially formed integrated circuit having a substrate structure; forming a first thick insulating layer on said substrate; forming at least one contact hole through said insulating layer; depositing a thin nucleation layer on said first insulating layer; patterning said thin nucleation layer; forming a second thick insulating layer on said first insulating layer and said patterned thin nucleation layer; forming an opening in said second insulating layer to expose said patterned thin nucleation layer; and selectively depositing a conductor in said opening, said patterned thin nucleation layer serving as a nucleation site for said selective deposition.
Claim 2
Dependent Claim 114 words
A process for forming a conductive interconnection in an integrated circuit structure, comprising the steps of: providing a partially formed integrated circuit having a substrate structure; forming a first thick insulating layer on said substrate; forming at least one contact hole through said insulating layer; depositing a thin nucleation layer on said first insulating layer; patterning said thin nucleation layer; forming a second thick insulating layer on said first insulating layer and said patterned thin nucleation layer; forming an opening in said second insulating layer to expose said patterned thin nucleation layer; and selectively depositing a conductor in said opening, said patterned thin nucleation layer serving as a nucleation site for said selective deposition.
Claim 3
Dependent Claim 33 words
The process of claim 1 wherein said opening in said second insulating layer is formed by etching said second insulating layer, said thin nucleation layer serving as an etch stop for said etching.
Claim 4
Dependent Claim 27 words
The process of claim 1 further comprising the step of filling said contact hole with a conductive material prior to said depositing of said thin nucleation layer.
Claim 5
Dependent Claim 51 words
The process of claim 3 wherein said step of filling said contact hole comprises the steps of: forming a contact nucleation layer of said substrate at the bottom of said contact hole; and selectively depositing a conductive material in said contact hole using said contact nucleation layer as a nucleation site.
Claim 6
Dependent Claim 32 words
The process of claim 3 wherein said thin nucleation layer covers the walls of said contact hole and covers the exposed portion of said substrate, said selective deposition filling said contact hole.
Claim 7
Dependent Claim 19 words
The process of claim 1 wherein said thin nucleation layer comprises a Titanium-Tungsten alloy and said conductor comprises Tungsten.
Claim 8
Dependent Claim 173 words
A process for forming a conductive interconnection in an integrated circuit structure, comprising the steps of: providing a partially formed integrated circuit having a substrate structure; forming a first thick insulating layer on said substrate; depositing a thin nucleation layer on said first insulating layer; patterning said thin nucleation layer, said patterned nucleation layer having a contact opening exposing said first thick insulating layer for formation of a contact hole; forming a second thick insulating layer on said first insulating layer and said patterned thin nucleation layer; forming an etch mask for patterning said second insulating layer; etching said second insulating layer using said etch mask to provide an opening in said second thick insulating layer, said opening exposing said patterned thin nucleation layer; forming said contact hole in said first insulating layer using said thin nucleation layer and said etch mask to as a pattern for etching said first insulating layer; selectively depositing a conductor in said opening, said patterned thin nucleation layer serving as a nucleation site for said selective deposition.
Claim 9
Dependent Claim 173 words
A process for forming a conductive interconnection in an integrated circuit structure, comprising the steps of: providing a partially formed integrated circuit having a substrate structure; forming a first thick insulating layer on said substrate; depositing a thin nucleation layer on said first insulating layer; patterning said thin nucleation layer, said patterned nucleation layer having a contact opening exposing said first thick insulating layer for formation of a contact hole; forming a second thick insulating layer on said first insulating layer and said patterned thin nucleation layer; forming an etch mask for patterning said second insulating layer; etching said second insulating layer using said etch mask to provide an opening in said second thick insulating layer, said opening exposing said patterned thin nucleation layer; forming said contact hole in said first insulating layer using said thin nucleation layer and said etch mask to as a pattern for etching said first insulating layer; selectively depositing a conductor in said opening, said patterned thin nucleation layer serving as a nucleation site for said selective deposition.
Claim 10
Dependent Claim 33 words
The process of claim 7 wherein said opening in said second insulating layer is formed by etching said second insulating layer, said thin nucleation layer serving as an etch stop for said etching.
Claim 11
Dependent Claim 19 words
The process of claim 7 wherein said thin nucleation layer comprises a Titanium-Tungsten alloy and said conductor comprises Tungsten.
Claim 12
Dependent Claim 188 words
A process for forming a conductive interconnection in an integrated circuit structure, comprising the steps of: providing a partially formed integrated circuit having a substrate structure; forming a first thick insulating layer on said substrate; depositing a etch stop layer on said first insulating layer; patterning said etch stop layer, said patterned etch stop layer having a contact opening exposing said first thick insulating layer for formation of a contact hole; forming a second thick insulating layer on said first insulating layer and said etch stop layer; forming an etch mask for patterning said second insulating layer; etching said second insulating layer using said etch mask to provide an opening in said second thick insulating layer, said opening exposing said etch stop layer; forming said contact hole in said first insulating layer using said etch stop layer and said etch mask to as a pattern for etching said first insulating layer; forming a thin nucleation layer on said etch stop layer and in said contact hole; and selectively depositing a conductor in said opening, said patterned thin nucleation layer serving as a nucleation site for said selective deposition.
Claim 13
Dependent Claim 188 words
A process for forming a conductive interconnection in an integrated circuit structure, comprising the steps of: providing a partially formed integrated circuit having a substrate structure; forming a first thick insulating layer on said substrate; depositing a etch stop layer on said first insulating layer; patterning said etch stop layer, said patterned etch stop layer having a contact opening exposing said first thick insulating layer for formation of a contact hole; forming a second thick insulating layer on said first insulating layer and said etch stop layer; forming an etch mask for patterning said second insulating layer; etching said second insulating layer using said etch mask to provide an opening in said second thick insulating layer, said opening exposing said etch stop layer; forming said contact hole in said first insulating layer using said etch stop layer and said etch mask to as a pattern for etching said first insulating layer; forming a thin nucleation layer on said etch stop layer and in said contact hole; and selectively depositing a conductor in said opening, said patterned thin nucleation layer serving as a nucleation site for said selective deposition.
Claim 14
Dependent Claim 33 words
The process of claim 10 wherein said opening in said second insulating layer is formed by etching said second insulating layer, said etch stop layer serving as an etch stop for said etching.
Claim 15
Dependent Claim 19 words
The process of claim 10 wherein said thin nucleation layer comprises a Titanium-Tungsten alloy and said conductor comprises Tungsten.

References Cited (Backward Citations)

US4283439A Cited
US4582563A Cited
US4624864A Cited
US4640738A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-10-07 1995-04-08 1995-10-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-10-07 1999-04-08 1999-10-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-10-07 2003-04-08 2003-10-08 $7700.00 Window Closed / Lapsed

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