US4736236A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tape bonding material and structure for electronic circuit fabrication
Assignee: Olin Corp
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Filing: 1986-07-25
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Granted: 1988-04-05
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Expires: 2006-07-25
Abstract
Abstract An electronic circuit assembly is disclosed including a semiconductor die having an aluminum therminal pad on its top surface. A lead frame is disposed adjacent the semiconductor die and is adapted to be electrically connected to the die. An electrical connection device interconnects the terminal pad to the lead frame. The electrical connection device includes a biclad transport tape comprising a first member formed from a nickel containing material and a second member formed from a copper containing material. The transport tape is disposed in the electronic circuit assembly with its first member bonded to the terminal pad and its second member bonded to the lead frame. The transport tape may be constructed so as to efficiently dissipate heat from the semiconductor die.
Inventors
- 👤 Sheldon H. Butt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:08
CPC Classifications
H; H10; H10W; H10W72/00; H10W72/701; H10W40/00; H10W40/70; H10W40/77; H10W70/00; H10W70/40; H10W70/421; H10W70/438; H10W70/456; H10W70/457; H10W72/50; H10W72/551; H10W72/552; H10W72/5522; H10W72/5524; H10W74/00
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
202 words
A transport tape adapted for electrically interconnecting at least one terminal pad on a semiconductor die to at least one of a plurality of leads; said transport tape comprising: a plurality of interconnect tape fingers, at least tape fingers adapted to be bonded at a first end to said terminal pad and further adapted to be bonded at a second end to one of said plurality of leads; said transport tape further comprising: a first layer of about 20 to about 40% nickel and the remainder copper, and having a yield strength of at least about 60,000 psi, said first layer for reducing the formation of intermetallics and being adapted for bonding to said terminal pad; a second layer formed from a copper containing material having a yield strength less than about 40,000 psi, said second layer being a softer material than said first layer and adapted to be bonded to one of said plurality of leads; a third layer formed of a copper alloy having a yield strength of at least 60,000 psi and a conductivity of at least about 50% IACS; said second and third layers being in direct contact with opposing sides of said first layer and bonded thereto.
Claim 2
Dependent Claim
202 words
A transport tape adapted for electrically interconnecting at least one terminal pad on a semiconductor die to at least one of a plurality of leads; said transport tape comprising: a plurality of interconnect tape fingers, at least tape fingers adapted to be bonded at a first end to said terminal pad and further adapted to be bonded at a second end to one of said plurality of leads; said transport tape further comprising: a first layer of about 20 to about 40% nickel and the remainder copper, and having a yield strength of at least about 60,000 psi, said first layer for reducing the formation of intermetallics and being adapted for bonding to said terminal pad; a second layer formed from a copper containing material having a yield strength less than about 40,000 psi, said second layer being a softer material than said first layer and adapted to be bonded to one of said plurality of leads; a third layer formed of a copper alloy having a yield strength of at least 60,000 psi and a conductivity of at least about 50% IACS; said second and third layers being in direct contact with opposing sides of said first layer and bonded thereto.
Claim 3
Dependent Claim
12 words
The transport tape of claim 1 including said second layer being copper.
Claim 4
Dependent Claim
63 words
The transport tape of claim 1 further including: a semiconductor die having at least one terminal pad thereon; a lead frame having a plurality of leads; and at least one of said tape fingers having the first end of said first layer bonded to said terminal pad and the second end of said second layer bonded to one of said plurality of leads.
Claim 5
Dependent Claim
197 words
A transport tape adapted for electrically interconnecting at least first and second terminal pads on a semiconductor die to at least one of a plurality of leads, said transport tape comprising: a plurality of interconnected tape fingers, at least one of said tape fingers having a first end section adapted to be bonded at either end of said end section to said first and second terminal pads, said first end section being shaped into an arch between the ends of said end section, said arch adapted to minimize the tendency of the tape to sag and contact said die, said at least one of said tape fingers further having a second end section adapted to be bonded to one of said plurality of leads, said transport tape further comprising: a first layer formed of a copper containing material having a yield strength of at least about 60,000 psi and a conductivity of at least about 50% IACS, and a second layer formed from a nickel containing material, said second layer being in direct contact with and bonded to said first layer and further adapted for connection to said first and second terminal pads on said semiconductor die.
Claim 6
Dependent Claim
197 words
A transport tape adapted for electrically interconnecting at least first and second terminal pads on a semiconductor die to at least one of a plurality of leads, said transport tape comprising: a plurality of interconnected tape fingers, at least one of said tape fingers having a first end section adapted to be bonded at either end of said end section to said first and second terminal pads, said first end section being shaped into an arch between the ends of said end section, said arch adapted to minimize the tendency of the tape to sag and contact said die, said at least one of said tape fingers further having a second end section adapted to be bonded to one of said plurality of leads, said transport tape further comprising: a first layer formed of a copper containing material having a yield strength of at least about 60,000 psi and a conductivity of at least about 50% IACS, and a second layer formed from a nickel containing material, said second layer being in direct contact with and bonded to said first layer and further adapted for connection to said first and second terminal pads on said semiconductor die.
Claim 7
Dependent Claim
44 words
The transport tape of claim 4 further comprising a third layer formed from a copper containing material, said third layer being in direct contact with and bonded to said second layer, said third layer further being adapted to be connected to said lead frame.
Claim 8
Dependent Claim
20 words
The transport tape of claim 5 including said third layer having a yield strength of less than about 40,000 psi.
Claim 9
Dependent Claim
12 words
The transport tape of claim 6 including said third layer being copper.
Claim 10
Dependent Claim
19 words
The transport tape of claim 7 including said second layer being up to 100% nickel and the remainder copper.
Claim 11
Dependent Claim
70 words
The transport tape of claim 5 further including: a semiconductor die having at least first and second terminal pads thereon; a lead frame having a plurality of leads; and at least one of said tape fingers having a first end section bonded at either end of said first end section to said first and second terminal pads and a second end section bonded to one of said plurality of leads.
Claim 12
Dependent Claim
44 words
The transport tape of claim 4 including at least a second tape finger having substantially the same structure as said first tape finger; and connection bar means connecting said first and second tape fingers adapted to enhance the heat dissipation from said semiconductor die.
Claim 13
Dependent Claim
41 words
The transport tape of claim 9 wherein said connection bar means further includes a ring means affixed to at least said first and second tape fingers for strengthening said first and second tape fingers and for improving the heat transfer therefrom.
Claim 14
Dependent Claim
27 words
The transport tape of claim 10 further including a conductive bonding means disposed between and bonded to said first and second tape fingers and said ring means.
Claim 15
Dependent Claim
149 words
A sag resistant tape having a plurality of metal fingers each adapted for electrically interconnecting at least one terminal pad on a semiconductor die to one of a plurality of external leads; said tape comprising: a clad material formed of a softer metal or alloy layer, a first high strength alloy layer and a second high strength alloy layer, said softer layer and said second high strength alloy layer, bonded onto opposing sides of said first high strength alloy layer; said first high strength layer comprising a copper alloy having a yield strength of at least about 60,000 psi for resisting sag in the tape; said second high strength layer having a yield strength of at least about 60,000 psi and a conductivity of at least about 50% IACS; and said softer layer being a metal or alloy having a yield strength substantially less than said high strength layers.
Claim 16
Dependent Claim
149 words
A sag resistant tape having a plurality of metal fingers each adapted for electrically interconnecting at least one terminal pad on a semiconductor die to one of a plurality of external leads; said tape comprising: a clad material formed of a softer metal or alloy layer, a first high strength alloy layer and a second high strength alloy layer, said softer layer and said second high strength alloy layer, bonded onto opposing sides of said first high strength alloy layer; said first high strength layer comprising a copper alloy having a yield strength of at least about 60,000 psi for resisting sag in the tape; said second high strength layer having a yield strength of at least about 60,000 psi and a conductivity of at least about 50% IACS; and said softer layer being a metal or alloy having a yield strength substantially less than said high strength layers.
Claim 17
Dependent Claim
21 words
The sag resistant tape of claim 13 wherein said softer layer has a yield strength of less than about 40,000 psi.
Claim 18
Dependent Claim
120 words
A sag resistant tape having a plurality of metal fingers each adapted for electrically interconnecting at least one terminal pad on a semiconductor die to a plurality of external leads, said tape comprising: a clad material formed of a high strength alloy layer and a softer metal or alloy layer; said high strength layer comprising a copper alloy having a yield strength of at least about 60,000 psi for resisting sag in the tape, said high strength layer having a conductivity of at least about 50% IACS; and said softer layer being a metal or alloy having a yield strength substantially less than said high strength layer, said softer layer having a yield strength of less than about 40,000 psi.
Claim 19
Dependent Claim
120 words
A sag resistant tape having a plurality of metal fingers each adapted for electrically interconnecting at least one terminal pad on a semiconductor die to a plurality of external leads, said tape comprising: a clad material formed of a high strength alloy layer and a softer metal or alloy layer; said high strength layer comprising a copper alloy having a yield strength of at least about 60,000 psi for resisting sag in the tape, said high strength layer having a conductivity of at least about 50% IACS; and said softer layer being a metal or alloy having a yield strength substantially less than said high strength layer, said softer layer having a yield strength of less than about 40,000 psi.
Claim 20
Dependent Claim
42 words
The sag resistant tape of claim 15 further including an alloy layer disposed between said bonded to said high strength alloy layer and to said softer layer for reducing the formation of intermetallics and being adapted for bonding to said terminal pad.
Claim 21
Dependent Claim
25 words
The sag resistant tape of claim 16 wherein said alloy layer for reducing intermetallics comprises about 20 to about 30% nickel and the remainder copper.
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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) | 1991-04-05 | 1991-10-05 | 1992-04-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-04-05 | 1995-10-05 | 1996-04-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-04-05 | 1999-10-05 | 2000-04-05 | $7700.00 | Window Closed / Lapsed |