Preparation of high conductivity copper films

• US 10,954,406 B2
• Filed: 02/02/2016
• Issued: 03/23/2021
• Est. Priority Date: 06/11/2015
• Status: Active Grant

• Current Assignee: National Research Council Canada
• Original Assignee: National Research Council Of Canada (Government of Canada)
• Inventors: Paquet, Chantal, Lacelle, Thomas, Malenfant, Patrick R. L.
• Primary Examiner(s): Klemanski, Helene
• Application Number:
  US15/835,688
• Publication Number:
  US 20180134909A1
• Time in Patent Office: 1,876 Days
• Field of Search: None
• CPC Class Codes: C08J 2379/08 Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
• CPC Class Codes: C08J 7/043 Improving the adhesiveness of the coatings per se, e.g. forming primers adhesives in the form of films or foils characterised by the primer layers between the polymer carriers and the adhesives C09J7/50
• CPC Class Codes: C08J 7/044 Forming conductive coatings; Forming coatings having anti-static properties
• CPC Class Codes: C08J 7/065 Low-molecular-weight organic substances, e.g. absorption of additives in the surface of the article
• CPC Class Codes: C08J 7/08 Heat treatment
• CPC Class Codes: C09D 11/033 characterised by the solvent
• CPC Class Codes: C09D 11/037 characterised by the pigment
• CPC Class Codes: C09D 11/32 characterised by colouring agents
• CPC Class Codes: C09D 11/36 based on non-aqueous solvents
• CPC Class Codes: C09D 11/52 Electrically conductive inks
• CPC Class Codes: H05K 1/0393 Flexible materials H05K1/038 takes precedence; specific organic compositions are classified in H05K1/0313 and subgroups
• CPC Class Codes: H05K 1/097 Inks comprising nanoparticles and specially adapted for being sintered at low temperature H05K1/095 takes precedence
• CPC Class Codes: H05K 2201/0145 Polyester, e.g. polyethylene terephthalate [PET], polyethylene naphthalate [PEN]
• CPC Class Codes: H05K 2201/0154 Polyimide
• CPC Class Codes: H05K 2201/0158 Polyalkene or polyolefin, e.g. polyethylene [PE], polypropylene [PP]
• CPC Class Codes: H05K 2201/0162 Silicon containing polymer, e.g. silicone
• CPC Class Codes: H05K 3/1283 After-treatment of the printed patterns, e.g. sintering or curing methods

Abstract

A copper precursor composition contains: a first copper complex of an imine or a first cyclic amine coordinated to a first copper precursor compound; and, a second copper complex of a primary amine or a second cyclic amine coordinated to a second copper precursor compound. A copper precursor composition contains a copper complex of an imine coordinated to a copper precursor compound. The copper precursor composition is thermally degradable at a temperature lower than a comparable composition containing only primary amine copper complexes under otherwise the same conditions to produce a metallic copper film having a resistivity of about 200 μΩ-cm or less. Inks containing the copper precursor composition and a solvent may be deposited on a substrate and sintered to produce a metallic copper film. The substrate with the film thereon is useful in electronic devices.

Claims

1. A copper precursor composition comprising:

a first copper complex comprising an imine or a first cyclic amine coordinated to a first copper precursor compound,

the imine comprising a compound of Formula (I)

2. The composition according to claim 1, wherein the first copper complex comprises two imines or two cyclic amines.

3. The composition according to claim 1, wherein the first copper complex comprises a cyclic amine, and the cyclic amine comprises a 6-membered ring.

4. The composition according to claim 3, wherein the 6-membered ring is pyridine or piperidine.

5. The composition according to claim 4, wherein the pyridine or piperidine is substituted with one or more C_1-8 alkyl groups.

6. The composition according to claim 1, wherein the first and second copper precursor compounds comprise copper (II) ions and one or more carboxylate anions coordinated to the copper (II) ions.

7. The composition according to claim 6, wherein the one or more carboxylate anions are two formate groups.

8. The composition according to claim 1, wherein the second copper complex comprises two primary amines.

9. The composition according to claim 1, wherein the primary amine is octylamine or ethylhexylamine.

10. The composition according to claim 1, wherein the first copper complex is present in the composition in an amount of about 20-75% (w/w) based on total weight of the first and second copper complexes.

11. The composition according to claim 1, wherein:

the first copper complex comprises the first cyclic amine, the first cyclic amine comprising a 5-membered, 6-membered or 7-membered ring structure, 1 to 30 carbon atoms and 1 to 3 nitrogen atoms where at least one nitrogen atom is in the ring structure and available for coordination to copper; and

,

the second copper complex comprises the primary amine.

12. The composition according to claim 11, wherein the time is 5 min or less.

13. A copper ink comprising the copper precursor composition as defined in claim 1 and a solvent.

14. The ink according to claim 13, wherein the copper precursor composition comprises 20-80 wt % of the ink based on total weight of the ink.

15. The ink according to claim 13 further comprising a binder.

16. A process for producing a metallic copper film comprising:

depositing the copper ink as defined in claim 13 on a surface of a substrate; and

, sintering the ink for about 10 min or less at a temperature of 140°

C. or less to produce a metallic copper film.

17. The process according to claim 16, wherein the temperature is 125°

C. or less.

18. The process according to claim 16, wherein the temperature is in a range of 100-130°

C.

19. The process according to claim 16, wherein the time is 5 min or less.

20. The process according to 16, wherein pressure during sintering is 2 atm or less.

21. The process according to 16, wherein the ink is deposited on the substrate by inkjet, screen, roll-to-roll, flexography or gravure printing.

22. The process according to 16, wherein the substrate comprises a flexible plastic.

23. The process according to claim 22, wherein the flexible plastic comprises polyethylene terephthalate (PET), polyolefin, polyethylene naphthalate (PEN), polydimethylsiloxane (PDMS), polystyrene, polycarbonate, polyimide or glass-reinforced epoxy resin laminate.