US5284796A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for flip chip connecting a semiconductor chip
Assignee: Fujitsu Ltd
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Filing: 1992-09-02
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Granted: 1994-02-08
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Expires: 2012-09-02
Abstract
Abstract A process for a flip chip connection of a semiconductor chip includes the steps of forming a plurality of stud bumps on the semiconductor chip, on which a plurality of solder bumps are formed, in the vicinity of the outer periphery thereof and on the outside of the solder bumps, providing a cut groove between a plurality of the solder bumps and the stud bumps, mating the solder bumps on the semiconductor chip and the corresponding solder bumps on the circuit board and heating for subsequent integration of the mating solder bumps, and breaking way the outer peripheral portion of the semiconductor chip along the cutting groove after a flip chip connection in order to remove the stud bumps.
Inventors
- 👤 Teru Nakanishi
- 👤 Kazuaki Karasawa
- 👤 Masayuki Ochiai
- 👤 Kaoru Hashimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:02
CPC Classifications
H; H10; H10W; H10W72/00; H10W72/071; H10W72/072; H05; H05K; H05K3/00; H05K3/30; H05K3/303; H05K3/32; H05K3/34; H05K3/341; H05K3/3431; H10W72/01; H10W72/012; H10W72/01221; H10W72/01225; H10W72/07202; H10W72/07204; H10W72/07221; H10W72/07227; H10W72/07231; H10W72/07236; H10W72/20; H10W72/241; H10W72/251; H10W72/252; H10W72/281; H10W72/285; H10W72/50; H10W72/551; H10W72/552; H10W72/5522; H10W72/5524
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
152 words
A process for flip chip connection of a semiconductor chip, in which solder bumps formed on the semiconductor chip in a matrix, arrangement are mated with a solder bumps formed on corresponding circuit board for flip chip connection, the process of said flip chip connection comprising the steps of: forming a plurality of stud bumps on the semiconductor chip, on which a plurality of solder bumps are formed in the vicinity of the outer periphery thereof and the outer side of said solder bumps; providing a cutting groove between a plurality of said solder bumps and said stud bumps; mating the solder bumps on said semiconductor chip and the corresponding solder bumps on said circuit board and heating for integration of the mating solder bumps; and breaking away the outer peripheral portion of said semiconductor chip along said cutting groove after a flip chip connection in order to remove said stud bumps.
Claim 2
Dependent Claim
152 words
A process for flip chip connection of a semiconductor chip, in which solder bumps formed on the semiconductor chip in a matrix, arrangement are mated with a solder bumps formed on corresponding circuit board for flip chip connection, the process of said flip chip connection comprising the steps of: forming a plurality of stud bumps on the semiconductor chip, on which a plurality of solder bumps are formed in the vicinity of the outer periphery thereof and the outer side of said solder bumps; providing a cutting groove between a plurality of said solder bumps and said stud bumps; mating the solder bumps on said semiconductor chip and the corresponding solder bumps on said circuit board and heating for integration of the mating solder bumps; and breaking away the outer peripheral portion of said semiconductor chip along said cutting groove after a flip chip connection in order to remove said stud bumps.
Claim 3
Dependent Claim
48 words
A process as set forth in claim 1, wherein said step of forming said stud bumps is performed by wire bonding a wire on a pad one time or a plurality of times in a repeated manner and by subsequently crushing the bonded wire to a desired height.
Claim 4
Dependent Claim
39 words
A process as set forth in claim 1, wherein each of said stud bumps is formed with a height higher than the height of the individual solder bumps but shorter than the total height of the mating solder bumps.
Claim 5
Dependent Claim
37 words
A process as set forth in claim 3, wherein the height of each of said stud bumps is selected so as to form a smaller diameter waist portion at an intermediate portion of the integrated solder bumps.
Claim 6
Dependent Claim
62 words
A flip chip connection method as set forth in claim 1, wherein said step of forming each said stud bump is performed by wire bonding and cutting a wire to a predetermined cut length and then crushing said predetermined cut length of wire into a length corresponding to the desired height of said stud bump and forming a tip end plane surface.
Claim 7
Dependent Claim
49 words
A process as set forth in claim 5, wherein the step of wire bonding and cutting is performed by initially cutting the wire to a length shorter than said predetermined cut length, and sequentially repeating the step until the length of the cut wire attains said predetermined cut length.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-02-07 | 1997-08-09 | 1998-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-02-07 | 2001-08-09 | 2002-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-02-07 | 2005-08-09 | 2006-02-08 | $7700.00 | Window Closed / Lapsed |