Coating metal foil with n-heterocyclic carbene compounds containing organic functionalities for improving metal-to-resin adhesion

Patent metadata

Field	Value
Publication number	US-2018168051-A1
Application number	US-201815882387-A
Country	US
Kind code	A1
Filing date	Jan 29, 2018
Priority date	Dec 2, 2014
Publication date	Jun 14, 2018
Grant date	—

Abstract

A carbene-coated metal foil is produced by applying an N-heterocyclic carbene (NHC) compound to one or more surfaces of a metal foil (e.g., an electrodeposited copper foil having a surface that is smooth and non-oxidized). The NHC compound contains a matrix-reactive pendant group that includes at least one of a vinyl-, allyl-, acrylic-, methacrylic-, styrenic-, amine-, amide- and epoxy-containing moiety capable of reacting with a base polymer (e.g., a vinyl-containing resin such as a polyphenylene oxide/triallyl-isocyanurate (PPO/TAIC) composition). The NHC compound may be synthesized by, for example, reacting a halogenated imidazolium salt (e.g., 1,3-bis(4-bromo-2,6-dimethylphenyl)-4,5-dihydro-1H-imidazol-3-ium chloride) and an organostannane having a vinyl-containing moiety (e.g., tributyl(vinyl)stannane) in the presence of a palladium catalyst. In some embodiments, an enhanced substrate for a printed circuit board (PCB) is produced by laminating the carbene-coated metal foil to a substrate that includes glass fiber impregnated with the base polymer.

First claim

What is claimed is:

1 . A method for producing a carbene-coated metal foil comprising:
providing a metal foil having a surface; applying an N-heterocyclic carbene (NHC) compound to the surface of the metal foil to form a carbene-coated metal foil, wherein the NHC compound comprises a matrix-reactive pendant group that includes at least one of a vinyl-, allyl-, acrylic-, methacrylic-, styrenic-, amine-, amide- and epoxy-containing moiety capable of reacting with a base polymer; drying the carbine-coated metal foil.

2 . The method as recited in claim 1 , wherein applying an N-heterocyclic carbene (NHC) compound to the surface of the metal foil to form a carbene-coated metal foil includes feeding an electrodeposited (ED) copper foil into a bath containing the NHC compound dissolved in a solvent.

3 . The method as recited in claim 2 , wherein the ED copper foil includes a conductive surface that is smooth and non-oxidized.

4 . The method as recited in claim 3 , wherein the NHC compound forms a monolayer on the smooth and non-oxidized conductive surface of the ED copper foil.

5 . The method as recited in claim 1 , wherein the NHC compound is represented by the following formula:

6 . The method as recited in claim 1 , wherein the NHC compound is represented by the following formula:

7 . The method as recited in claim 1 , wherein the NHC compound is represented by the following formula:

8 . A carbene-coated metal foil produced according to claim 1 .

9 . A method for producing a carbene-coated metal foil, comprising:
providing a metal foil having a surface; applying an N-heterocyclic carbene (NHC) compound to the surface of the metal foil to form a carbene-coated metal foil, wherein the NHC compound comprising a matrix-reactive pendant group selected from the group consisting of a vinyl-containing moiety, an allyl-containing moiety, an acrylic-containing moiety, a methacrylic-containing moiety, a styrenic-containing moiety, an amine-containing moiety, an amide-containing moiety, and an epoxy-containing moiety; drying the carbine-coated metal foil.

10 . The method as recited in claim 9 , wherein the NHC compound is a vinyl-functionalized NHC compound represented by the following formula:

and
further comprising synthesizing the vinyl-functionalized NHC compound by reacting 1,3-bis(4-bromo-2,6-dimethylphenyl)-4,5-dihydro-1H-imidazol-3-ium chloride with tributyl(vinyl)stannane via palladium-catalyzed Stille coupling.

11 . The method as recited in claim 10 , wherein applying an N-heterocyclic carbene (NHC) compound to the surface of the metal foil to form a carbene-coated metal foil includes feeding an electrodeposited (ED) copper foil into a bath containing the NHC compound dissolved in a solvent.

12 . The method as recited in claim 11 , wherein the ED copper foil includes a conductive surface that is smooth and non-oxidized.

13 . The method as recited in claim 12 , wherein the NHC compound forms a monolayer on the smooth and non-oxidized conductive surface of the ED copper foil.

14 . The method as recited in claim 9 , wherein the NHC compound is an acrylate-functionalized NHC compound represented by the following formula:

and
further comprising synthesizing the acrylate-functionalized NHC compound by reacting 1,3-bis(4-bromo-2,6-dimethylphenyl)-4,5-dihydro-1H-imidazol-3-ium chloride with tributyltin acrylate via palladium-catalyzed Stille coupling.

15 . The method as recited in claim 14 , wherein applying an N-heterocyclic carbene (NHC) compound to the surface of the metal foil to form a carbene-coated metal foil includes feeding an electrodeposited (ED) copper foil into a bath containing the NHC compound dissolved in a solvent.

16 . The method as recited in claim 15 , wherein the ED copper foil includes a conductive surface that is smooth and non-oxidized.

17 . The method as recited in claim 16 , wherein the NHC compound forms a monolayer on the smooth and non-oxidized conductive surface of the ED copper foil.

18 . The method as recited in claim 9 , wherein the NHC compound is a styrene-functionalized NHC compound represented by the following formula:

and
further comprising synthesizing the styrene-functionalized NHC compound by reacting 1,3-bis(4-bromo-2,6-dimethylphenyl)-4,5-dihydro-1H-imidazol-3-ium chloride with (z)-tributyl(4-vinyl styryl)stannane via palladium-catalyzed Stille coupling.

19 . The method as recited in claim 18 , wherein applying an N-heterocyclic carbene (NHC) compound to the surface of the metal foil to form a carbene-coated metal foil includes feeding an electrodeposited (ED) copper foil into a bath containing the NHC compound dissolved in a solvent.

20 . The method as recited in claim 19 , wherein the ED copper foil includes a conductive surface that is smooth and non-oxidized, and wherein the NHC compound forms a monolayer on the smooth and non-oxidized conductive surface of the ED copper foil.

Assignees

• IBM

Inventors

• Boday Dylan J
• Kuczynski Joseph
• Wertz Jason T
• Zhang Jing

Classifications

• B32B5/024

  Woven fabric · CPC title

• B32B2260/046

  Synthetic resin · CPC title

• H05K2203/122

  Organic non-polymeric compounds, e.g. oil, wax or thiol · CPC title

• B01J31/2278

  Complexes comprising two carbene ligands differing from each other, e.g. Grubbs second generation catalysts · CPC title

• H05K2203/0392

  Pretreatment of metal, e.g. before finish plating, etching · CPC title