Epoxy-siloxanes based electrically conductive adhesives for semiconductor assembly and process for use thereof

• US 6,548,175 B2
• Filed: 01/11/2001
• Issued: 04/15/2003
• Est. Priority Date: 01/11/2001
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Jackson, Raymond A., Sachdev, Krishna G., Perry, Charles H., Shannon, Megan J., Ostrander, Amy B.
• Primary Examiner(s): Moore, Margaret G.
• Assistant Examiner(s): Feely, Michael J
• Application Number:
  US09/759,012
• Publication Number:
  US 20020127406A1
• Time in Patent Office: 824 Days
• Field of Search: 428/413, 428/414, 428/418, 428/447, 428/448, 428/450, 427/387, 427/386, 427/96, 156/292, 156/326, 156/329, 156/330, 524/265, 524/439, 528/12, 528/14, 528/15, 528/33, 528/40, 523/400, 525/107
• US Class Current: 428/414
• CPC Class Codes: C08G 59/306 containing silicon
• CPC Class Codes: C08G 59/3254 containing atoms other than carbon, hydrogen, oxygen or nitrogen
• CPC Class Codes: C08G 59/38 together with di-epoxy compounds
• CPC Class Codes: C08L 63/00 Compositions of epoxy resins; Compositions of derivatives of epoxy resins
• CPC Class Codes: C09J 163/00 Adhesives based on epoxy resins; Adhesives based on derivatives of epoxy resins
• CPC Class Codes: C09J 9/02 Electrically-conducting adhesives
• CPC Class Codes: H01L 2224/13111 Tin [Sn] as principal constituent
• CPC Class Codes: H01L 2224/29101 the principal constituent melting at a temperature of less than 400°C
• CPC Class Codes: H01L 2224/29111 Tin [Sn] as principal constituent
• 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 2224/2929 with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/29339 Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/29344 Gold [Au] as principal constituent
• CPC Class Codes: H01L 2224/29364 Palladium [Pd] as principal constituent
• CPC Class Codes: H01L 2224/8319 Arrangement of the layer connectors prior to mounting
• CPC Class Codes: H01L 2224/838 Bonding techniques
• 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 2924/00014 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 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01039 : Yttrium [Y]
• CPC Class Codes: H01L 2924/01045 : Rhodium [Rh]
• CPC Class Codes: H01L 2924/01046 : Palladium [Pd]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/0105 : Tin [Sn]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/01087 : Francium [Fr]
• CPC Class Codes: H01L 2924/0132 : Binary Alloys
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/0665 : Epoxy resin
• CPC Class Codes: H01L 2924/0781 : being an ohmic electrical conductor
• CPC Class Codes: H01L 2924/09701 : Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/10253 : Silicon [Si]
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/15787 : Ceramics, e.g. crystalline carbides, nitrides or oxides
• CPC Class Codes: H01L 2924/1579 : with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/19043 : being a resistor
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding
• CPC Class Codes: H01L 2924/351 : Thermal stress
• CPC Class Codes: H01L 2924/3512 : Cracking
• CPC Class Codes: H05K 3/321 : by conductive adhesives
• CPC Class Codes: Y10T 428/31511 : Of epoxy ether
• CPC Class Codes: Y10T 428/31515 : As intermediate layer
• CPC Class Codes: Y10T 428/31663 : As siloxane, silicone or silane

Abstract

The invention is directed to improved conductive adhesives for solder-free interconnections in microelectronic assembly processes such as for chip carrier-to-substrate attachment. These adhesives are characterized by low tensile modulus, low resistivity, high adhesion strength, and durability of these properties during reliability stress conditions of thermal shock, thermal aging, and temperature/humidity (85° C./85%) exposure of the assembled devices. The adhesives contain a homogeneous solution of a siloxane containing epoxide, a curing agent, a curing catalyst and an organic polymeric or oligomeric additive. A conductive filler is added to the solution forming the filler. Preferred fillers are Ag coated with Pd and Ag coated with Au.

Claims

1. A curable epoxy-siloxane based solvent-free conductive adhesive resin composition comprising:

a siloxane comprising at least two epoxy-functional groups, or mixtures thereof;

a curing agent;

a curing catalyst;

an organic polymeric or oligomeric additive; and

a conductive filler selected form the group consisting of Ag coated with palladium, Ag coated with Au, and mixtures thereof;

wherein the siloxane, the curing agent, curing catalyst, and polymer additive are mutually soluble.

2. The composition of claim 1, wherein the siloxane is represented by the formula:

wherein x=2-4;

y=1-5;

R is an alkyl radical represented by the formula C_nH_2n+1, where n=1-4;

R′

is the same as R or a 3,3,3-trifluoropropyl radical represented by the formula—

CH₂CH₂CF₃.

3. The composition of claim 2 wherein the curing agent is an anhydride.

4. The composition of claim 3, wherein the polymeric or oligomeric additive is selected from the group consisting of:

polyacrylate, polymethacrylate, polyalkylacrylate, polyalkylmethacrylate, and perfluoro alkyl acrylate;

wherein the alkyl group in said polyalkylacrylate, polyalkylmethacrylate, or perfluoro alkyl acrylate has 1 to 8 carbon atoms.

5. The composition of claim 4 wherein the siloxane is selected from the group consisting of bis(1,3-glycidoxy propyl) tetramethyl disiloxane and bis(1,5-glycidoxy propyl) hexamethyl trisiloxane and mixtures thereof.

6. The composition of claim 5 wherein the curing agent is selected from the group consisting of hexahydrophthalic anhydride and 4-methylhexahydrophthalic anhydride, and mixtures thereof.

7. The composition of claim 5 wherein the curing agent is selected from the group consisting of dodecenyl succinic anhydride, maleic anhydride, methyl nadic anhydride, and mixture thereof.

8. An electronic component article of manufacture comprising:

a substrate having disposed thereon a cured conductive adhesive composition; and

an object bonded to said substrate using said adhesive;

wherein said adhesive composition is the adhesive composition according to claim 1.

9. The electronic component article of manufacture of claim 8, wherein said object is a semiconductor chip carrier.

10. The electronic component article of manufacture of claim 8, wherein said object is an electronic component, and said substrate is a circuit board.

11. The electronic component article of manufacture of claim 8, wherein the siloxane of said adhesive composition is represented by the formula:

wherein x=2-4;

y=1-5;

R is an alkyl radical represented by the formula C_nH_2n+1, where n=1-4 ;

R′

is the same as R or a 3,3,3-trifluoropropyl radical represented by the formula—

CH₂CH₂CF₃.

12. The electronic component article of manufacture of claim 8, wherein:

the siloxane of said adhesive composition is represented by the formula;

wherein x=2-4;

y=1-5;

R is an alkyl radical represented by the formula C_nH_2n+1, where n=1-4;

R′

is the same as R or a 3,3,3-trifluoropropyl radical represented by the formula —

CH₂CH₂CF₃;

the curing agent of said adhesive composition is an anhydride; and

the polymeric or oligomeric additive of said adhesive composition is selected from the group consisting of;

polyacrylate, polymethacrylate, polyalkylacrylate, polyalkylmethacrylate, perfluoro alkyl acrylate,

wherein the alkyl group in said polyalkylacrylate, polyalkylmethacrylate, or perfluoro alkyl acrylate has 1 to 8 carbon atoms.

13. A method for making an electronic component assembly which requires attachment of separate components comprising the steps of:

applying the conductive adhesive of claim 1 onto one of the components to be bonded;

placing the other component to be bonded on the adhesive of the adhesive coated component; and

curing the adhesive to attach the components.

14. The method of claim 13, wherein the siloxane of said adhesive is represented by the formula:

wherein x=2-4;

y=1-5;

R is an alkyl radical represented by the formula C_nH_2n+1, where n=1-4;

R′

is the same as R or a 3,3,3-trifluoropropyl radical represented by the formula—

CH₂CH₂CF₃.

15. The method of claim 13 wherein:

the siloxane of said adhesive is represented by the formula;

wherein x=2-4;

y=1-5;

R is an alkyl radical represented by the formula C_nH_2n+1, where n=1-4;

R′

is the same as R or a 3,3,3-trifluoropropyl radical represented by the formula—

CH₂CH₂CF₃;

the curing agent of said adhesive is an anhydride; and

the polymeric or oligomeric additive of said adhesive is selected from the group consisting of;

polyacrylate, polymethacrylate, polyalkylacrylate, polyalkylmethacrylate, perfluoro alkyl acrylate,

wherein the alkyl group in said polyalkylacrylate, polyalkylmethacrylate, or perfluoro alkyl acrylate has 1 to 8 carbon atoms.