US4754912A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controlled collapse thermocompression gang bonding
Assignee: National Semiconductor Corp
•
Filing: 1987-11-16
•
Granted: 1988-07-05
•
Expires: 2007-11-16
Abstract
Abstract Controlled shape bumps are fabricated into the metal contact fingers that are to be used in the gang bonding assembly of semiconductor devices. The bump shape permits the gang bonding of a plurality of contact fingers simultaneously while producing reliable, uniformly high strength bonds.
Inventors
- 👤 Carmen D. Burns
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:47
CPC Classifications
H; H10; H10W; H10W72/00; H10W72/60; H10W70/00; H10W70/40; H10W70/421; H10W70/424; H10W72/01; H10W72/016; H10W72/071; H10W72/073; H10W72/07331; H10W72/07336; H10W72/07337; H10W72/076; H10W72/07631; H10W72/07632; H10W72/07633; H10W72/30; H10W72/351; H10W72/353; H10W72/354; H10W90/00; H10W90/701; H10W90/761; H10W90/764
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
181 words
The method of making contact with the contact pads arrayed on a semiconductor device comprising the steps: creating a tape having a succession of metal finger patterns with each pattern having inwardly extending portions terminating in tips that form an array that mates with said contact pads on said semiconductor device, said tips having transversely extending bumps adapted for thermocompression gang bonding to said contact pads, each said bump being configured to have a columnar form in which the bonding face is smaller than the bump portion adjacent to said finger and wherein said bump has a substantially trapezoidal cross section and a substantially flat bonding face that is parallel with the plane of said finger; making said substantially flat bonding face slightly convex; locating said tape so that said tips of said finger patterns are in registry with the contact pads of a semiconductor device; and pressing a heated bonding tool against said finger tips on the face opposite said bumps whereby said bumps are deformed by self limiting collapse and are thereby thermocompression gang bonded to said contact pads.
Claim 2
Independent Claim
181 words
The method of making contact with the contact pads arrayed on a semiconductor device comprising the steps: creating a tape having a succession of metal finger patterns with each pattern having inwardly extending portions terminating in tips that form an array that mates with said contact pads on said semiconductor device, said tips having transversely extending bumps adapted for thermocompression gang bonding to said contact pads, each said bump being configured to have a columnar form in which the bonding face is smaller than the bump portion adjacent to said finger and wherein said bump has a substantially trapezoidal cross section and a substantially flat bonding face that is parallel with the plane of said finger; making said substantially flat bonding face slightly convex; locating said tape so that said tips of said finger patterns are in registry with the contact pads of a semiconductor device; and pressing a heated bonding tool against said finger tips on the face opposite said bumps whereby said bumps are deformed by self limiting collapse and are thereby thermocompression gang bonded to said contact pads.
Claim 3
Dependent Claim
24 words
The process of claim 1 including the step of making said bump bonding face to have a width of about 1.5 to 2.0 mils.
Claim 4
Dependent Claim
16 words
The process of claim 2 including the step of gold plating said fingers prior to bonding.
Claim 5
Dependent Claim
37 words
The process of claim 1 including the additional steps of: excising said fingers from said tape thereby producing a semiconductor device with metal fingers extending outwardly therefrom; and bonding said extending fingers to a secondary metal structure.
Claim 6
Dependent Claim
15 words
The process of claim 4 including the further step of encapsulating the thus produced device.
References Cited (Backward Citations)
US3440027A
Cited
US3589000A
Cited
US3680206A
Cited
US3625837A
Cited
US3832769A
Cited
US3825353A
Cited
US3882532A
Cited
US3859718A
Cited
US3838984A
Cited
US3868724A
Cited
US4072982A
Cited
US4010885A
Cited
US4007479A
Cited
US4143385A
Cited
US4210926A
Cited
JPS54140465A
Cited
US4259436A
Cited
US4209355A
Cited
US4308339A
Cited
US4312926A
Cited
US4331831A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-07-05 | 1992-01-04 | 1992-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-05 | 1996-01-04 | 1996-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-05 | 2000-01-04 | 2000-07-05 | $7700.00 | Window Closed / Lapsed |