Process for producing multilayer printed wiring board
Multilayer printed wiring boards superior in formation of an ultrafine wiring, which can form a conductive layer superior in peel strength on a flat insulating layer surface, can be prepared by a method including the following steps (A)-(E): (A) a step of laminating a film with a metal film, wherein a metal film layer is formed on a support layer, on an internal-layer circuit substrate via a curable resin composition layer, or laminating an adhesive film with a metal film, wherein a curable resin composition layer is formed on a metal film layer of the film with a metal film, on an internal-layer circuit substrate; (B) a step of curing a curable resin composition layer to form an insulating layer; (C) a step of removing a support layer; (D) a step of removing a metal film layer; and (E) a step of forming a metal film layer on an insulating layer surface by electroless plating.
1. A method of producing a multilayer printed wiring board, comprising:
(A) laminating (i) a film with a first metal film, wherein said film with a first metal film comprises a first metal film layer formed on a support layer, on (ii) an internal-layer circuit substrate via a curable resin composition layer;
(B) curing said curable resin composition layer to form an insulating layer;
(C) removing said support layer;
(D) removing all of said first metal film layer; and
(E) forming a second metal film layer on said insulating layer surface by electroless plating.
2. A method according to claim 1 , wherein said first metal film layer is not formed by applying a preformed metal foil to said support layer.
3. A method according to claim 1 , wherein said first metal film layer is formed by one or more kinds of methods selected from the group consisting of a vapor deposition method, a sputtering method and an ion plating method.
4. A method according to claim 1 , wherein said first metal film layer is formed from copper.
5. A method according to claim 1 , wherein said second metal film layer is formed from copper.
6. A method according to claim 1 , wherein the insulating layer surface, after removing said first metal film layer, has an arithmetic mean roughness (Ra) of not more than 200 nm.
7. A method according to claim 1 , wherein the insulating layer surface, after removing said first metal film layer, has an arithmetic mean roughness (Ra) of not more than 80 nm.
8. A method according to claim 1 , further comprising:
(F) forming a blind via after (B) curing said curable resin composition layer to form an insulating layer or (C) removing said support layer.
9. A method according to claim 8 , further comprising:
(G) conducting desmearing after (F) forming a blind via.
10. A method according to claim 1 , further comprising:
(H) forming a conductive layer by electroplating after (E) forming a second metal film layer on an insulating layer surface by electroless plating.
11. A method according to claim 1 , wherein a release layer is present between said support layer and said first metal film layer.
12. A method according to claim 11 , wherein said release layer is formed from one or more kinds of water-soluble polymers selected from the group consisting of a water-soluble cellulose resin, a water-soluble polyester resin and a water-soluble acrylic resin.
13. A method according to claim 12 , wherein said water-soluble polyester resin is a water-soluble polyester having a sulfo group or a salt thereof and/or a carboxyl group or a salt thereof, and said water-soluble acrylic resin is a water-soluble acrylic resin having a carboxyl group or a salt thereof.
14. A method according to claim 11 , further comprising:
(I) removing said release layer after (C) removing said support layer.
15. A method according to claim 11 , wherein said release layer has a layer thickness of 0.01 μm to 20 μm.
16. A method according to claim 1 , wherein said first metal film layer has a layer thickness of 25 nm to 5000 nm.
17. A method according to claim 1 , wherein said support layer has a layer thickness of 10 μm to 70 μm.
18. A method according to claim 1 , wherein said support layer has an arithmetic mean roughness (Ra) of not more than 50 nm.
19. A method according to claim 1 wherein said support layer is a plastic film.
20. A method according to claim 1 , wherein said support layer is a poly(ethylene terephthalate) film.
21. A method according to claim 1 , wherein said curable resin composition comprises a component having a hetero atom in a molecule.
22. A method according to claim 1 , wherein said curable resin composition comprises a component having a nitrogen atom in a molecule.
23. A method according to claim 1 , wherein said curable resin composition comprises an epoxy resin and a curing agent.
24. A method according to claim 23 , wherein said curing agent comprises a nitrogen atom in a molecule.
25. A method according to claim 23 , wherein said curing agent is a triazine skeleton-containing phenol novolac resin and/or a triazine skeleton-containing cresol novolac resin.
26. A method according to claim 21 , wherein said curable resin composition further comprises a thermoplastic resin.
27. A method according to claim 21 , wherein said curable resin composition further comprises an inorganic filler.
28. A method according to claim 1 , wherein said curable resin composition layer is a prepreg comprised of a sheet-like reinforcing substrate made of fiber and impregnated with the curable resin composition.
29. A method of producing a multilayer printed wiring board, comprising:
(A) laminating (i) an adhesive film with a first metal film, wherein said adhesive film with a first metal film comprises a curable resin composition layer formed on a first metal film layer, wherein said first metal film layer is formed on a support layer on (ii) an internal-layer circuit substrate;
(B) curing said curable resin composition layer to form an insulating layer;
(C) removing said support layer;
(D) removing all of said first metal film layer; and
(E) forming a second metal film layer on said insulating layer surface by electroless plating.
30. A method according to claim 29 , wherein said first metal film layer is not formed by applying a preformed metal foil to said support layer.
31. A method according to claim 29 , wherein said first metal film layer is formed by one or more kinds of methods selected from the group consisting of a vapor deposition method, a sputtering method and an ion plating method.
32. A method according to claim 29 , wherein said first metal film layer is formed from copper.
33. A method according to claim 29 , wherein said second metal film layer is formed from copper.
34. A method according to claim 29 , wherein the insulating layer surface, after removing said first metal film layer, has an arithmetic mean roughness (Ra) of not more than 200 nm.
35. A method according to claim 29 , wherein the insulating layer surface, after removing said first metal film layer, has an arithmetic mean roughness (Ra) of not more than 80 nm.
36. A method according to claim 29 , further comprising:
(F) forming a blind via after (B) curing said curable resin composition layer to form an insulating layer or (C) removing said support layer.
37. A method according to claim 36 , further comprising:
(G) conducting desmearing after (F) forming a blind via.
38. A method according to claim 29 , further comprising:
(H) forming a conductive layer by electroplating after (E) forming a second metal film layer on an insulating layer surface by electroless plating.
39. A method according to claim 29 , wherein a release layer is present between said support layer and said first metal film layer.
40. A method according to claim 39 , wherein said release layer is formed from one or more kinds of water-soluble polymers selected from the group consisting of a water-soluble cellulose resin, a water-soluble polyester resin and a water-soluble acrylic resin.
41. A method according to claim 40 , wherein said water-soluble polyester resin is a water-soluble polyester having a sulfo group or a salt thereof and/or a carboxyl group or a salt thereof, and said water-soluble acrylic resin is a water-soluble acrylic resin having a carboxyl group or a salt thereof.
42. A method according to claim 39 , further comprising:
(I) removing said release layer after (C) removing said support layer.
43. A method according to claim 39 , wherein said release layer has a layer thickness of 0.01 μm to 20 μm.
44. A method according to claim 39 , wherein said first metal film layer has a layer thickness of 25 nm to 5000 nm.
45. A method according to claim 39 , wherein said support layer has a layer thickness of 10 μm to 70 μm.
46. A method according to claim 39 , wherein said support layer has an arithmetic mean roughness (Ra) of not more than 50 nm.
47. A method according to claim 39 wherein said support layer is a plastic film.
48. A method according to claim 39 , wherein said support layer is a poly(ethylene terephthalate) film.
49. A method according to claim 39 , wherein said curable resin composition comprises a component having a hetero atom in a molecule.
50. A method according to claim 39 , wherein said curable resin composition comprises a component having a nitrogen atom in a molecule.
51. A method according to claim 39 , wherein said curable resin composition comprises an epoxy resin and a curing agent.
52. A method according to claim 51 , wherein said curing agent comprises a nitrogen atom in a molecule.
53. A method according to claim 51 , wherein said curing agent is a triazine skeleton-containing phenol novolac resin and/or a triazine skeleton-containing cresol novolac resin.
54. A method according to claim 49 , wherein said curable resin composition further comprises a thermoplastic resin.
55. A method according to claim 49 , wherein said curable resin composition further comprises an inorganic filler.
56. A method according to claim 29 , wherein said curable resin composition layer is a prepreg comprised of a sheet-like reinforcing substrate made of fiber and impregnated with the curable resin composition.