High fatigue ductility electrodeposited copper foil

• US 6,132,887 A
• Filed: 05/24/1996
• Issued: 10/17/2000
• Est. Priority Date: 06/16/1995
• Status: Expired due to Term

• Current Assignee: Nikko Materials USA, Inc. (Eternal Materials Co., Ltd.)
• Original Assignee: Gould Electronics Incorporated (Eternal Materials Co., Ltd.)
• Inventors: Schneider, Bernd, Clouser, Sidney J., Bohmler, Ulrike, Apperson, R. Duane, Wiechmann, Rudolf
• Primary Examiner(s): Morris, Terrell
• Assistant Examiner(s): JUSKA, CHERYL ANN
• Application Number:
  US08/647,706
• Time in Patent Office: 1,607 Days
• Field of Search: 428/472, 428/469, 428/606, 428/607, 428/674, 428/675, 428/676, 205/50, 205/76, 205/77, 205/291
• US Class Current: 428/606
• CPC Class Codes: C25D 1/04 Wires; Strips; Foils
• CPC Class Codes: C25D 5/10 Electroplating with more than one layer of the same or of different metals for bearings C25D7/10
• 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 1/09 Use of materials for the conductive, e.g. metallic pattern
• CPC Class Codes: H05K 2201/0355 Metal foils
• CPC Class Codes: H05K 2203/0307 Providing micro- or nanometer scale roughness on a metal surface, e.g. by plating of nodules or dendrites
• CPC Class Codes: H05K 2203/0723 Electroplating, e.g. finish plating
• CPC Class Codes: H05K 2203/1105 Heating or thermal processing not related to soldering, firing, curing or laminating, e.g. for shaping the substrate or during finish plating
• CPC Class Codes: H05K 3/384 by plating
• CPC Class Codes: Y10T 428/12 All metal or with adjacent metals
• CPC Class Codes: Y10T 428/12431 Foil or filament smaller than 6 mils
• CPC Class Codes: Y10T 428/12438 Composite
• CPC Class Codes: Y10T 428/12903 Cu-base component

Abstract

This invention relates to an annealable electrodeposited copper foil having a substantially uniform unoriented grain structure that is essentially columnar grain free, said foil being characterized by a fatigue ductility of at least about 25% after being annealed at 177° C. for 15 minutes. In one embodiment, the foil is annealed, said foil being characterized by a fatigue ductility of at least about 65%. The invention also relates to a process for making an electrodeposited copper foil using an electrolyte solution characterized by a critical concentration of chloride ions of up to about 5 ppm and organic additives of up to about 0.2 ppm.

Claims

1. A heat treated electrodeposited copper foil having a substantially uniform unoriented grain structure that is essentially columnar grain free;

said foil being electrodeposited using an electrolyte solution containing no organic additives and having a chloride ion concentration of up to about 5 ppm; and

said foil being heat treated at a temperature in excess of about 200°

C. for at least about 30 minutes and capable of enduring about 260 to about 500 flex cycles prior to breaking.

2. The foil of claim 1 wherein said foil is annealed, said foil being characterized by a fatigue ductility of at least about 65%.

3. The foil of claim 1 wherein said foil has an ultimate tensile strength at 23°

C. in the range of about 60,000 to about 95,000 psi prior to being heat treated.

4. The foil of claim 1 wherein said foil has an elongation at 23°

C. in the range of about 8% to about 18% prior to being heat treated.

5. The foil of claim 1 wherein said foil has an ultimate tensile at 180°

C. in the range of about 22,000 to about 32,000 psi.

6. The foil of claim 1 wherein said foil has an elongation at 180°

C. in the range of about 24% to about 45%.

7. The foil of claim 2 wherein said foil has an ultimate tensile strength at 23°

C. in the range of about 36,000 to about 48,000 psi.

8. The foil of claim 2 wherein said foil has an elongation at 23°

C. in the range of about 23% to about 36%.

9. The foil of claim 2 wherein said foil has an ultimate tensile strength at 180°

C. in the range of about 22,000 to about 32,000 psi.

10. The foil of claim 2 wherein said foil has an elongation at 180°

C. in the range of about 25% to about 48%.

11. The foil of claim 1 wherein the average grain size for said foil is up to about 3 microns.

12. The foil of claim 1 wherein the average grain size for said foil after being annealed at 177°

C. for 15 minutes is up to about 5 microns.

13. The foil of claim 2 wherein the average grain size for said foil is up to about 8 microns.

14. The foil of claim 1 wherein the foil has a matte side raw foil R_tm in the range of about 1 to about 10 microns.

15. The foil of claim 1 wherein the foil has a shiny side raw foil R_tm of less than about 6 microns.

16. The foil of claim 1 with at least one roughened layer of copper or copper oxide applied to one or both sides of said foil.

17. The foil of claim 1 with at least one metallic layer applied to one or both sides of said foil, the metal in said metallic layer being selected from the group consisting of indium, zinc, tin, nickel, cobalt, copper-zinc mixture or alloy, copper-tin mixture or alloy, and zinc-nickel mixture or alloy.

18. The foil of claim 1 with at least one metallic layer applied to one or both sides of said foil, the metal in said metallic layer being selected from the group consisting of tin, chromium, chromium-zinc mixture or alloy, zinc, and zinc nickel mixture or alloy.

19. The foil of claim 1 with at least one roughened layer of copper or copper oxide applied to one or both sides of said foil, at least one first metallic layer applied to said roughened layer, the metal in said first metallic layer being selected from the group consisting of indium, zinc, tin, nickel, cobalt, copper-zinc mixture or alloy, copper-tin mixture or alloy, and zinc-nickel mixture or alloy, and at least one second metallic layer applied to said first metallic layer, the metal in said second metallic layer being selected from the group consisting of tin, chromium, chromium-zinc mixture or alloy, zinc, and zinc-nickel mixture or alloy.

20. The foil of claim 1 with at least one silane coupling agent overlying one or both sides of said foil.

21. The foil of claim 1 wherein said foil is electrodeposited using an electrolyte solution characterized by a chloride ion concentration of up to about 3 ppm.

22. The foil of claim 1 wherein said foil has an ultimate tensile strength at 23°

C. in the range of about 42,000 to about 70,000 psi after being annealed at 177°

for 15 minutes and prior to being heat treated.

23. The foil of claim 1 wherein said foil has an elongation at 23°

C. in the range of about 15% to about 31% after being annealed at 177°

C. for 15 minutes and prior to being heat treated.

24. The foil of claim 1 wherein said foil has an ultimate tensile strength at 180°

C. in the range of about 22,000 to about 32,000 psi after being annealed at 177°

C. for 15 minutes and prior to being heat treated.

25. The foil of claim 1 wherein said foil has an elongation at 180°

C. in the range of about 24% to about 45% after being annealed at 177°

C. for 15 minutes and prior to being heat treated.