US5270255A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Metallization process for good metal step coverage while maintaining useful alignment mark
Assignee: GlobalFoundries Singapore Pte Ltd
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Filing: 1993-01-08
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Granted: 1993-12-14
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Expires: 2013-01-08
Abstract
Abstract A new method of metallization of an integrated circuit is described. Semiconductor device structures are fabricated in and on a semiconductor substrate. At least one contact opening to the semiconductor substrate and at least one lithography alignment cross mark opening structure are formed. A barrier layer is preferably sputtered within the contact openings and over the semiconductor device structures. A cold aluminum seed layer is sputtered over all surfaces of the contact openings. Next, a hot aluminum flow layer is provided to obtain the desired step coverage of the contact openings. A second cold aluminum layer is then sputtered onto the hot aluminum layer to define the edges of the wide lithography alignment marks while maintaining good contact opening coverage.
Inventors
- 👤 George Wong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:30
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/042; H10W20/045; H10W20/033; H10W20/056; H10W46/00; H10W46/101; H10W46/501; Y; Y10; Y10S; Y10S148/00; Y10S148/102
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
124 words
The method of metallization of an integrated circuit while maintaining an effective alignment cross mark structure comprising: providing semiconductor device structures in and on a semiconductor substrate; providing at least one contact opening to said semiconductor substrate and an alignment cross mark opening structure on said semiconductor structure; cold sputtering an aluminum seed layer conformally and completely covering all surfaces of said contact openings and said cross mark opening structure; hot sputtering an aluminum layer which flows aluminum into said contact openings and said cross mark openings; and cold sputtering an aluminum layer over said hot layer which is a directional deposition that forms cusp-like edges in the wide said alignment cross mark opening structure and which obtains said effective alignment cross mark structure.
Claim 2
Independent Claim
124 words
The method of metallization of an integrated circuit while maintaining an effective alignment cross mark structure comprising: providing semiconductor device structures in and on a semiconductor substrate; providing at least one contact opening to said semiconductor substrate and an alignment cross mark opening structure on said semiconductor structure; cold sputtering an aluminum seed layer conformally and completely covering all surfaces of said contact openings and said cross mark opening structure; hot sputtering an aluminum layer which flows aluminum into said contact openings and said cross mark openings; and cold sputtering an aluminum layer over said hot layer which is a directional deposition that forms cusp-like edges in the wide said alignment cross mark opening structure and which obtains said effective alignment cross mark structure.
Claim 3
Dependent Claim
24 words
The method of claim 1 wherein a barrier layer is located under said aluminum seed layer and said barrier layer is composed of TiW.
Claim 4
Dependent Claim
35 words
The method of claim 1 wherein a barrier layer is located under said aluminum seed layer and said barrier layer is composed of TiN and has a thickness of between about 1000 to 1500 Angstroms.
Claim 5
Dependent Claim
32 words
The method of claim 1 wherein said cold aluminum seed layer is deposited at a temperature of less than about 200° C. to a thickness of between about 1500 and 2000 Angstroms.
Claim 6
Dependent Claim
38 words
The method of claim 1 wherein said hot metal flow layer is deposited at a temperature of between about 475° to 550° C. to a thickness of between about 2000 to 4000 Angstroms to obtain desired step coverage.
Claim 7
Dependent Claim
35 words
The method of claim 1 wherein said cold aluminum layer over said hot layer is deposited at a temperature of less than about 200° C. to a thickness of between about 2000 to 5000 Angstroms.
Claim 8
Independent Claim
130 words
The method of metallization of an integrated circuit comprising: providing semiconductor device structures in and on a semiconductor substrate; providing a first metallization layer within said device structures; providing at least one contact opening to said first metallization layer; providing at least one lithography alignment cross mark opening structure among said device structures; cold sputtering an aluminum seed layer conformally and completely covering all surfaces of said contact openings and said cross mark opening structure; hot sputtering an aluminum layer which flows hot aluminum into said contact openings and said cross mark openings; and cold sputtering an aluminum layer over said hot layer which is a directional deposition that forms cusp-like edges in the wide said alignment cross mark opening structure and which obtains said effective alignment cross mark structure.
Claim 9
Independent Claim
130 words
The method of metallization of an integrated circuit comprising: providing semiconductor device structures in and on a semiconductor substrate; providing a first metallization layer within said device structures; providing at least one contact opening to said first metallization layer; providing at least one lithography alignment cross mark opening structure among said device structures; cold sputtering an aluminum seed layer conformally and completely covering all surfaces of said contact openings and said cross mark opening structure; hot sputtering an aluminum layer which flows hot aluminum into said contact openings and said cross mark openings; and cold sputtering an aluminum layer over said hot layer which is a directional deposition that forms cusp-like edges in the wide said alignment cross mark opening structure and which obtains said effective alignment cross mark structure.
Claim 10
Dependent Claim
24 words
The method of claim 7 wherein a barrier layer is located under said aluminum seed layer and said barrier layer is composed of TiW.
Claim 11
Dependent Claim
34 words
The method of claim 7 wherein barrier layer is located under said aluminum seed layer and said barrier layer is composed of TiN and has a thickness of between about 1000 to 1500 Angstroms.
Claim 12
Dependent Claim
32 words
The method of claim 7 wherein said cold aluminum seed layer is deposited at a temperature of less than about 200° C. to a thickness of between about 1500 and 2000 Angstroms.
Claim 13
Dependent Claim
38 words
The method of claim 7 wherein said hot metal flow layer is deposited at a temperature of between about 475° to 550° C. to a thickness of between about 2000 to 4000 Angstroms to obtain desired step coverage.
Claim 14
Dependent Claim
35 words
The method of claim 8 wherein said cold aluminum layer over said hot layer is deposited at a temperature of less than about 200° C. to a thickness of between about 2000 to 5000 Angstroms.
References Cited (Backward Citations)
US4520554A
Cited
JPS6039829A
Cited
JPS63311741A
Cited
US4981529A
Cited
US4936930A
Cited
JPH01272133A
Cited
US5106781A
Cited
US5002902A
Cited
US5106432A
Cited
US4970176A
Cited
US5108951A
Cited
US5175125A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-12-13 | 1997-06-14 | 1997-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-12-13 | 2001-06-14 | 2001-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-12-13 | 2005-06-14 | 2005-12-14 | $7700.00 | Window Closed / Lapsed |