US6268293B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming wires on an integrated circuit chip
Assignee: International Business Machines Corp
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Filing: 1999-11-18
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Granted: 2001-07-31
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Expires: 2019-11-18
Abstract
Abstract A damascene method of forming conductive lines in an integrated circuit chip. Trenches are etched by a plasma formed by capacitively coupling a gas mixture at 500 to 3000 watts under a pressure of 50-400 mTorr. The gas mixture includes 2-30 sccm of C 4 F 8 , 20-80 sccm of CO, 2-30 sccm of O 2 and 50-400 sccm of Ar. Gas flow can be adjusted to an optimum level, thereby achieving a high degree of uniformity. Wafers falling below a selected uniformity may be reworked. A damascene wiring layer formed in the trenches with an acceptable flow exhibit a high degree of sheet resistance uniformity and improved line to line shorts yield.
Inventors
- 👤 Lawrence Clevenger
- 👤 Greg Costrini
- 👤 Dave Dobuzinsky
- 👤 Yoichi Otani
- 👤 Thomas Rupp
- 👤 Viraj Sardesai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:16
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10W; H10W20/00; H10W20/01; H10W20/071; H10W20/081
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
141 words
A damascene method of forming metal lines on an integrated circuit chip, said method comprising: a) forming a plurality of trenches in a dielectric layer on the surface of a semiconductor wafer by flowing a mixture of gasses at a rate of 2-30 sccm of C 4 F 8 , 20-80 sccm of CO, 2-30 sccm of O2 and 50-400 sccm of Ar over the wafer surface; b) measuring trench uniformity across said semiconductor wafer which exceeds a maximum variation; c) adjusting the flow conditions of said gasses within the aforestated range of rates to optimize the rate of flow of said gasses to form said trenches within said maximum variation; d) re-measuring trench uniformity across said semiconductor wafer below said maximum variation; and e) filling said trenches with metal only when said trench uniformity is measured below said maximum variation.
Claim 2
Dependent Claim
141 words
A damascene method of forming metal lines on an integrated circuit chip, said method comprising: a) forming a plurality of trenches in a dielectric layer on the surface of a semiconductor wafer by flowing a mixture of gasses at a rate of 2-30 sccm of C 4 F 8 , 20-80 sccm of CO, 2-30 sccm of O2 and 50-400 sccm of Ar over the wafer surface; b) measuring trench uniformity across said semiconductor wafer which exceeds a maximum variation; c) adjusting the flow conditions of said gasses within the aforestated range of rates to optimize the rate of flow of said gasses to form said trenches within said maximum variation; d) re-measuring trench uniformity across said semiconductor wafer below said maximum variation; and e) filling said trenches with metal only when said trench uniformity is measured below said maximum variation.
Claim 3
Dependent Claim
32 words
A damascene method of forming metal lines as in claim 1 , wherein said flow of gases is capacitively coupled at 1500 watts and maintained at a pressure range of 86 mTorr.
Claim 4
Dependent Claim
25 words
A damascene method of forming metal lines as in claim 2 , wherein C 4 F 8 is flowed at a rate of 8-10 sccm.
Claim 5
Dependent Claim
25 words
A damascene method of forming metal lines as in claim 3 , wherein C 4 F 8 is flowed at a rate of 8 sccm.
Claim 6
Dependent Claim
25 words
A damascene method of forming metal lines as in claim 3 , wherein C 4 F 8 is flowed at a rate of 10 sccm.
Claim 7
Dependent Claim
22 words
A damascene method of forming metal lines as in claim 2 , wherein CO is flowed at a rate of 40 sccm.
Claim 8
Dependent Claim
23 words
A damascene method of forming metal lines as in claim 2 , wherein O 2 is flowed at a rate of 8-10 sccm.
Claim 9
Dependent Claim
23 words
A damascene method of forming metal lines as in claim 7 , wherein O 2 is flowed at a rate of 8 sccm.
Claim 10
Dependent Claim
23 words
A damascene method of forming metal lines as in claim 7 , wherein O 2 is flowed at a rate of 10 sccm.
Claim 11
Dependent Claim
22 words
A damascene method of forming metal lines as in claim 2 , wherein Ar is flowed at a rate of 160 sccm.
Claim 12
Dependent Claim
21 words
A damascene method as in claim 1 wherein in step b) there is measured width and depth uniformity of the trenches.
Claim 13
Dependent Claim
31 words
A damascene method as in claim 11 wherein in step d) width and depth uniformity of the trenches formed in said dielectric layer have a 1σ variation of less than 2.5%.
References Cited (Backward Citations)
US5770098A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-07-30 | 2005-01-29 | 2005-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-07-30 | 2009-01-29 | 2009-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-07-30 | 2013-01-29 | 2013-07-31 | $7700.00 | Window Closed / Lapsed |