METHOD FOR PRODUCING CIRCUIT BOARD
A method for producing a wiring board according to the present disclosure includes: (A) forming a first insulating material layer on a supporting substrate; (B) forming a first opening part in the first insulating material layer; (C) forming a seed layer on the first insulating material layer; (D) providing a resist pattern on a surface of the seed layer; (E) forming a wiring part including a pad and wiring; (F) removing the resist pattern; (G) removing the seed layer; (H) applying a first surface treatment to the surface of the pad; (I) forming a second insulating material layer; (J) forming a second opening part in the second insulating material layer; (K) applying a second surface treatment to the surface of the pad; and (L) heating the second insulating material layer to a temperature equal to or higher than the glass transition temperature of the second insulating material layer.
1 . A method for producing a wiring board, the method comprising steps of:
(A) forming a first insulating material layer on a supporting substrate;
(B) forming a first opening part in the first insulating material layer;
(C) forming a seed layer on a surface of the first insulating material layer by electroless plating;
(D) providing a resist pattern for wiring part formation on a surface of the seed layer;
(E) forming a wiring part including a pad and wiring by electrolytic plating in a region exposed from the resist pattern on the surface of the seed layer;
(F) removing the resist pattern;
(G) removing the exposed seed layer by removal of the resist pattern;
(H) applying a first surface treatment to a surface of the pad;
(I) forming a second insulating material layer so as to cover the wiring part;
(J) forming a second opening part at a position corresponding to the pad in the second insulating material layer;
(K) applying a second surface treatment to the surface of the pad; and
(L) heating the second insulating material layer to a temperature equal to or higher than a glass transition temperature of the second insulating material layer.
2 . The method for producing a wiring board according to claim 1 , wherein a surface treatment agent is used in the step of applying the first surface treatment, and the surface treatment agent is removed from the surface of the pad in the step of applying the second surface treatment.
3 . The method for producing a wiring board according to claim 2 , wherein the surface treatment agent used for the first surface treatment includes an organic component for improving an adhesiveness between the wiring part and the second insulating material layer.
4 . The method for producing a wiring board according to claim 1 , wherein the second surface treatment is at least one selected from the group consisting of an oxygen plasma treatment, an argon plasma treatment, and a desmear treatment.
5 . The method for producing a wiring board according to claim 1 , wherein an average roughness Ra of a surface of the wiring part that has been subjected to the first surface treatment is 40 to 80 nm.
6 . The method for producing a wiring board according to claim 1 , wherein after step (J), a peel strength of the second insulating material layer is 0.2 to 0.7 kN/m with respect to the wiring.
7 . The method for producing a wiring board according to claim 1 , further comprising a step of removing residue on the first insulating material layer and/or inside the first opening part, between step (B) and step (C).
8 . The method for producing a wiring board according to claim 1 , wherein at least one of the first insulating material layer and the second insulating material layer includes a photosensitive resin.
9 . The method for producing a wiring board according to claim 11 wherein the resist pattern has a groove-shaped opening having a line width of 0.5 to 20 μm.