Low temperature flexible die attach adhesive and articles using same

• US 5,386,000 A
• Filed: 12/03/1993
• Issued: 01/31/1995
• Est. Priority Date: 10/24/1990
• Status: Expired due to Term

• Current Assignee: National Starch and Chemical Investment Holding Corporation (Ingredion Incorporated)
• Original Assignee: Johnson Matthey Incorporated (Johnson Matthey PLC)
• Inventors: Nguyen, My N.
• Primary Examiner(s): Kight, III, John
• Assistant Examiner(s): COONEY, JOHN M
• Application Number:
  US08/162,389
• Time in Patent Office: 424 Days
• Field of Search: 528/363, 528/422, 528/362, 523/400, 523/416, 252/512, 252/514
• US Class Current: 528/362
• CPC Class Codes: C07C 261/02 Cyanates
• CPC Class Codes: C08G 59/4007 Curing agents not provided for by the groups C08G59/42 - C08G59/66
• CPC Class Codes: C08K 5/0016 Plasticisers
• CPC Class Codes: C08L 79/04 Polycondensates having nitrogen-containing heterocyclic rings in the main chain; Polyhydrazides; Polyamide acids or similar polyimide precursors
• CPC Class Codes: C09J 179/04 Polycondensates having nitrogen-containing heterocyclic rings in the main chain; Polyhydrazides; Polyamide acids or similar polyimide precursors
• CPC Class Codes: H01B 1/22 the conductive material comprising metals or alloys
• CPC Class Codes: H01L 2224/29 of an individual layer connector
• CPC Class Codes: H01L 2224/29099 Material
• CPC Class Codes: H01L 2224/2919 with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/29199 Material of the matrix
• CPC Class Codes: H01L 2224/2929 with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/29299 Base material
• CPC Class Codes: H01L 2224/29339 Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/8319 Arrangement of the layer connectors prior to mounting
• CPC Class Codes: H01L 2224/8385 using a polymer adhesive, e.g. an adhesive based on silicone, epoxy, polyimide, polyester
• CPC Class Codes: H01L 23/3737 Organic materials with or without a thermoconductive filler
• CPC Class Codes: H01L 23/4828 Conductive organic material or pastes, e.g. conductive adhesives, inks
• CPC Class Codes: H01L 23/49855 for flat-cards, e.g. credit cards cards per se G06K19/00
• CPC Class Codes: H01L 24/29 of an individual layer connector
• CPC Class Codes: H01L 24/83 using a layer connector
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00013 : Fully indexed content
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01023 : Vanadium [V]
• CPC Class Codes: H01L 2924/01027 : Cobalt [Co]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/0665 : Epoxy resin
• CPC Class Codes: H01L 2924/07802 : not being an ohmic electrical conductor
• CPC Class Codes: H01L 2924/10253 : Silicon [Si]
• CPC Class Codes: H01L 2924/15747 : Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2924/3512 : Cracking

Abstract

Described is a flexible adhesive formulation for bonding a semiconductor device to a flexible substrate and a flexible card containing a semiconductor device which can be processed in a computer.

Claims

1. A flexible adhesive formulation having a ROC value of about 1 meter or above comprising the reaction product of a cyanate ester-containing material and at least one flexibilizer miscible with cyanate ester in the uncured state selected from the group consisting of elastomeric and thermoplastic modifiers selected from the group consisting of hydroxyl, amine, and epoxide reactive functional group containing compounds and mixtures thereof, said cyanate ester comprising a least 15 wt. % of the mixture to be reacted and said flexibilizer having a glass transition temperature less than about 25°

C.

2. A flexible adhesive formulation according to claim 1 further comprising silver in an amount sufficient to function as a curing catalyst and to render said adhesive curable in not greater than 5 minutes at 200°

C.

3. A flexible adhesive formulation according to claim 1 further comprising an alkylphenol, a metal-containing curing catalyst and an electrically and/or thermally conductive filler.

4. A flexible adhesive formulation according to claim 3 wherein said filler comprises silver in an amount of 60 to 90 wt. % of the formulation.

5. A flexible adhesive formulation according to claim 3 comprising 0.01 to 0.06 wt. % metal curing catalyst, 0.5 to 2 wt. % alkylphenol and up to 90 wt. % silver.

6. A flexible adhesive formulation according to claim 5 comprising 4 to 20 wt. % silver.

7. A flexible adhesive formulation according to claim 1 further comprising an electrically and/or thermally conductive filler.

8. A flexible adhesive formulation according to claim 7 comprising 60 to 90 wt. % silver.

9. A flexible adhesive formulation according to claim 1 further comprising up to 90 wt. % silver.