Printed wiring board and method for manufacturing the same

• US 20070128855A1
• Filed: 12/07/2006
• Published: 06/07/2007
• Est. Priority Date: 12/07/2005
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: Oh, Sung, Joung, Jae, Cho, Hye
• Granted Patent: US 7,713,862 B2
• Time in Patent Office: Days
• US Class Current: 438/637
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: H05K 2201/0154 Polyimide
• CPC Class Codes: H05K 2201/09881 Coating only between conductors, i.e. flush with the conductors
• CPC Class Codes: H05K 2203/013 Inkjet printing, e.g. for printing insulating material or resist using ink-jet printing to form a conductive pattern H05K3/125
• CPC Class Codes: H05K 3/125 by ink-jet printing
• CPC Class Codes: H05K 3/4647 by applying an insulating layer around previously made via studs
• CPC Class Codes: H05K 3/4664 Adding a circuit layer by thick film methods, e.g. printing techniques or by other techniques for making conductive patterns by using pastes, inks or powders H05K3/4647 takes precedence

Abstract

Provided is a method for manufacturing a printed wiring board, which can enhance the peel strength between an insulating layer and a conductive pattern by a two-step process, that is, a semi-hardening and full-hardening of the insulating layer. In the method for manufacturing the printed wiring board having one or more layers of a conductive pattern and an insulating pattern, an insulating pattern is formed on an insulating substrate, and at least one of the insulating substrate and the insulating pattern is semi-hardened. A conductive pattern is formed on the insulating substrate and/or the insulating pattern, thereby providing a stack structure. Then, a thermal treatment is performed on the stack structure to fully harden the semi-hardened insulating substrate and/or insulating pattern, and the conductive pattern is fired.

Claims

1. A method for manufacturing a printed wiring board having one or more layers of a conductive pattern and an insulating pattern, comprising the step of:

forming an insulating pattern on an insulating substrate;

semi-hardening at least one of the insulating substrate and the insulating pattern;

forming a conductive pattern on the insulating substrate and/or the insulating pattern, thereby providing a stack structure;

performing a thermal treatment on the stack structure to fully harden the semi-hardened insulating substrate and/or insulating pattern; and

firing the conductive pattern.

2. The method of claim 1, wherein at least one of the insulating substrate, the conductive pattern, and the insulating pattern is formed using an inkjet process.

3. The method of claim 1, wherein the conductive pattern and the insulating pattern are simultaneously formed on the same layer using an inkjet process.

4. The method of claim 1, wherein the semi-hardening is performed by ultraviolet (UV) irradiation.

5. The method of claim 4, further comprising the step of performing a drying process before the semi-hardening.

6. The method of claim 3, wherein the insulating substrate and the insulating pattern are formed of an insulating ink by an inkjet process, and the insulating ink is a 3-component system consisting of polyamic acid, photo-polymerization initiator, and crosslinking agent.

7. The method of claim 6, wherein the polyamic acid is 50-60 wt %, the crosslinking agent is 21-35 wt %, and the photo-polymerization agent is 5-29 wt %.

8. The method of claim 3, wherein the insulating substrate and the insulating pattern are formed of an insulating ink by an inkjet process, and the insulating ink is a 2-component system consisting of bismaleimide based compound and photo-polymerization initiator.

9. The method of claim 8, wherein the bismaleimide based compound is 85-95 wt % and the photo-polymerization initiator is 5-15 wt %.

10. The method of claim 3, wherein the conductive pattern is formed of a conductive ink by an inkjet process, and the conductive ink includes at least one metal selected from the group consisting of gold, silver, copper, platinum, chrome, nickel, aluminum, titan, palladium, tin, vanadium, zinc, manganese, cobalt, zirconium, and alloys thereof.

11. The method of claim 1, wherein the thermal treatment is performed at 200-350°

C.

32. A printed wiring board manufactured by the method of claim 1.

12. A method for manufacturing a printed wiring board, comprising the steps of:

(a) printing an insulating ink using an inkjet process to form an insulating substrate;

(b) semi-hardening the insulating ink;

(c) printing a conductive ink on the semi-hardened insulating substrate along a wiring pattern by an inkjet process, thereby forming a first conductive pattern;

(d) printing a conductive ink on a partial upper portion of the first conductive pattern by an inkjet process, thereby forming an interlayer conductive layer;

(e) printing an insulating ink on the insulating substrate and the first conductive pattern along a wiring pattern by an inkjet process, thereby forming an insulating pattern; and

(f) performing a thermal treatment to harden the insulating ink and fire the conductive ink.

13. The method of claim 12, further comprising the steps of:

semi-hardening a second insulating pattern after the step (e); and

repeating the steps (c) to (e) more than one time, thereby forming a multi-layered circuit.

14. The method of claim 12, wherein the semi-hardening is performed by ultraviolet (UV) irradiation.

15. The method of claim 14, further comprising the step of performing a drying process before the semi-hardening.

16. The method of claim 12, wherein the insulating ink is a 3-component system consisting of polyamic acid, photo-polymerization initiator, and crosslinking agent.

17. The method of claim 16, wherein the polyamic acid is 50-60 wt %, the crosslinking agent is 21-35 wt %, and the photo-polymerization agent is 5-29 wt %.

18. The method of claim 12, wherein the insulating ink is a 2-component system consisting of bismaleimide based compound and photo-polymerization initiator.

19. The method of claim 18, wherein the bismaleimide based compound is 85-95 wt % and the photo-polymerization initiator is 5-15 wt %.

20. The method of claim 12, wherein the conductive pattern is formed of a conductive ink by an inkjet process, and the conductive ink includes at least one metal selected from the group consisting of gold, silver, copper, platinum, chrome, nickel, aluminum, titan, palladium, tin, vanadium, zinc, manganese, cobalt, zirconium, and alloys thereof.

21. The method of claim 12, wherein the thermal treatment is performed at 200-350°

C.

22. A method for manufacturing a printed wiring board, comprising the steps of:

(a) printing an insulating ink using an inkjet process to form an insulating substrate;

(b) semi-hardening the insulating ink;

(c) printing a conductive ink and an insulating ink on the semi-hardened insulating substrate along a wiring pattern by an inkjet process, thereby forming a first conductive pattern and a first insulating pattern;

(d) semi-hardening the first insulating pattern;

(e) printing a conductive ink and an insulating ink on the first conductive pattern and the first insulating pattern along a wiring pattern by an inkjet process, thereby forming a second insulating pattern and a second conducive pattern acting as an interlayer conducive layer; and

(f) performing a thermal treatment to harden the insulating ink and fire the conductive ink.

23. The method of claim 22, further comprising the steps of:

semi-hardening the second insulating pattern after the step (e); and

repeating the steps (c) to (e) more than one time, thereby forming a multi-layered circuit.

24. The method of claim 22, wherein the semi-hardening is performed by ultraviolet (UV) irradiation.

25. The method of claim 24, further comprising the step of performing a drying process before the semi-hardening.

26. The method of claim 22, wherein the insulating ink is a 3-component system consisting of polyamic acid, photo-polymerization initiator, and crosslinking agent.

27. The method of claim 26, wherein the polyamic acid is 50-60 wt %, the crosslinking agent is 21-35 wt %, and the photo-polymerization agent is 5-29 wt %.

28. The method of claim 22, wherein the insulating ink is a 2-component system consisting of bismaleimide based compound and photo-polymerization initiator.

29. The method of claim 28, wherein the bismaleimide based compound is 85-95 wt % and the photo-polymerization initiator is 5-15 wt %.

30. The method of claim 22, wherein the conductive pattern is formed of a conductive ink by an inkjet process, and the conductive ink includes at least one metal selected from the group consisting of gold, silver, copper, platinum, chrome, nickel, aluminum, titan, palladium, tin, vanadium, zinc, manganese, cobalt, zirconium, and alloys thereof.

31. The method of claim 22, wherein the thermal treatment is performed at 200-350°

C.