Patent US4787958A successfully refreshed from Google Patents.
US4787958A
Expired / Lapsed
US
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Method of chemically etching TiW and/or TiWN
Assignee: NXP USA Inc
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Filing: 1987-08-28
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Granted: 1988-11-29
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Expires: 2007-08-28
Abstract
Abstract A method of chemically etching TiW and/or TiWN is described wherein the etching of a semiconductor substrate having a layers of TiWN, TiW and Au disposed between the substrate and a Au bump is performed with a 30% solution of hydrogen peroxide (H 2 O 2 ) at a temperature of approximately 90° C.
Inventors
- 👤 William H. Lytle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:02
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/32; C23F1/38; H; H10; H10P; H10P50/00; H10P50/60; H10P50/66; H10P50/663; H10P50/667; Y; Y10; Y10S; Y10S257/00; Y10S257/915
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
93 words
A method of chemically etching a semiconductor device comprising: providing a semiconductor device having a substrate, a layer of titanium-tungsten-nitride coupled to said substrate, a layer of titanium-tungsten coupled to said layer of titanium-tungsten-nitride, and a metal contact coupled to a first portion of said titanium-tungsten layer; and etching said titanium-tungsten and titanium-tungsten-nitride layers in a 30% solution of hydrogen peroxide at a temperature between approximately 80°-90° C. to remove a second portion of said titanium-tungsten layer and a portion of said titanium-tungsten-nitride layer adjacent said second portion of said titanium tungsten layer.
Claim 2
Independent Claim
93 words
A method of chemically etching a semiconductor device comprising: providing a semiconductor device having a substrate, a layer of titanium-tungsten-nitride coupled to said substrate, a layer of titanium-tungsten coupled to said layer of titanium-tungsten-nitride, and a metal contact coupled to a first portion of said titanium-tungsten layer; and etching said titanium-tungsten and titanium-tungsten-nitride layers in a 30% solution of hydrogen peroxide at a temperature between approximately 80°-90° C. to remove a second portion of said titanium-tungsten layer and a portion of said titanium-tungsten-nitride layer adjacent said second portion of said titanium tungsten layer.
Claim 3
Dependent Claim
22 words
The method of claim 1 further comprising providing a layer of gold disposed between said layer of titanium-tungsten and said metal contact.
Claim 4
Dependent Claim
11 words
The method of claim 1 wherein said metal contact is gold.
Claim 5
Independent Claim
90 words
A method of chemically etching a semiconductor device comprising: providing a semiconductor device having a substrate, a layer of titanium-tungsten-nitride coupled to said substrate, a layer of titanium-tungsten coupled to said layer of titanium-tungsten-nitride, a layer of gold coupled to said layer of titanium-tungsten, and a metal contact coupled to a first portion of said gold layer; etching said layer of gold to remove a portion not coupled to said metal contact; and etching said titanium-tungsten and titaium-tungsten-nitride layers in a 30% solution of hydrogen peroxide at approximately 80°-90° C.
Claim 6
Independent Claim
90 words
A method of chemically etching a semiconductor device comprising: providing a semiconductor device having a substrate, a layer of titanium-tungsten-nitride coupled to said substrate, a layer of titanium-tungsten coupled to said layer of titanium-tungsten-nitride, a layer of gold coupled to said layer of titanium-tungsten, and a metal contact coupled to a first portion of said gold layer; etching said layer of gold to remove a portion not coupled to said metal contact; and etching said titanium-tungsten and titaium-tungsten-nitride layers in a 30% solution of hydrogen peroxide at approximately 80°-90° C.
Claim 7
Dependent Claim
10 words
The method claim 4 wherein said metal contact is gold.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-11-29 | 1992-05-30 | 1992-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-11-29 | 1996-05-30 | 1996-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-11-29 | 2000-05-30 | 2000-11-29 | $7700.00 | Window Closed / Lapsed |