US4970571A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bump and method of manufacturing the same
Assignee: Toshiba Corp
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Filing: 1988-09-23
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Granted: 1990-11-13
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Expires: 2008-09-23
Abstract
Abstract According to the present invention, there is provided a method for forming a bump and comprising the steps of dipping a semiconductor element with an Al electrode and a passivation film formed thereon in a palladium solution containing 5 to 2,000 ppm of at least one element selected from the group consisting of Zn, Pb, Sn, Cd, and Cr, selectively precipitating palladium on the electrode, and conducting electroless nickel-plating on the semiconductor element, including the electrode on which palladium is precipitated.
Inventors
- 👤 Koji Yamakawa
- 👤 Nobuo Iwase
- 👤 Michihiko Inaba
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:12
CPC Classifications
H; H10; H10W; H10W72/00; H10W72/01; H10W72/012; H10W72/019; H10W72/20; H10W72/221; H10W72/222; H10W72/223; H10W72/251; H10W72/252; H10W72/255; H10W72/90; H10W72/921; H10W72/923; H10W72/951; H10W72/952
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
73 words
A method for forming a bump and comprising the steps of: dipping a semiconductor element with an Al electrode and a passivation film formed thereon in a palladium solution containing 5 to 2,000 ppm of at least one element selected from a group consisting of Zn, Pb, Sn, Cd, and Cr; selectively precipitating palladium on said electrode; and performing electroless nickel-plating on said semiconductor element, including said electrode on which palladium is precipitated.
Claim 2
Independent Claim
73 words
A method for forming a bump and comprising the steps of: dipping a semiconductor element with an Al electrode and a passivation film formed thereon in a palladium solution containing 5 to 2,000 ppm of at least one element selected from a group consisting of Zn, Pb, Sn, Cd, and Cr; selectively precipitating palladium on said electrode; and performing electroless nickel-plating on said semiconductor element, including said electrode on which palladium is precipitated.
Claim 3
Dependent Claim
26 words
A method according to claim 1, further including the step of annealing said semiconductor element at 100° to 500° C., after said step of electroless nickel-plating.
Claim 4
Dependent Claim
25 words
A method according to claim 1, further including a step of forming a copper layer on a nickel film, after said step of electroless nickel-plating.
Claim 5
Dependent Claim
25 words
A method according to claim 1, further including a step of forming a gold layer on a nickel film, after said step of electroless nickel-plating.
Claim 6
Dependent Claim
25 words
A method according to claim 1, further including a step of forming a solder layer on a nickel film, after said step of electroless nickel-plating.
Claim 7
Dependent Claim
14 words
A method according to claim 1, wherein said semiconductor element is an LSI chip.
Claim 8
Dependent Claim
36 words
A bump comprising: an Al electrode formed on a semiconductor element; and a palladium layer formed on said electrode and a bump material layer formed by electroless nickel plating which are alternatively laminated twice or more.
Claim 9
Dependent Claim
36 words
A bump comprising: an Al electrode formed on a semiconductor element; and a palladium layer formed on said electrode and a bump material layer formed by electroless nickel plating which are alternatively laminated twice or more.
Claim 10
Dependent Claim
19 words
A bump according to claim 7, wherein an Au layer is formed as the uppermost layer of said bump.
Claim 11
Dependent Claim
19 words
A bump according to claim 7, wherein an Sn layer is formed as the uppermost layer of said bump.
Claim 12
Dependent Claim
19 words
A bump according to claim 7, wherein a Cu layer is formed as the uppermost layer of said bump.
Claim 13
Dependent Claim
14 words
A bump according to claim 7, wherein said semiconductor element is an LSI chip.
Claim 14
Dependent Claim
14 words
A bump according to claim 7 wherein the material constituting the bump comprises nickel.
Claim 15
Dependent Claim
21 words
A bump according to claim 12 wherein the nickel is present in a proportion greater than the other element or elements.
References Cited (Backward Citations)
US4680610A
Cited
US4831432A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-11-12 | 1994-05-14 | 1994-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-12 | 1998-05-14 | 1998-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-12 | 2002-05-14 | 2002-11-13 | $7700.00 | Window Closed / Lapsed |