METHOD FOR PRODUCING WIRING BOARD
Provided is a method for manufacturing a wiring board in which unintentional release of a carrier during downsizing is suppressed and a first substrate can be reliably laminated onto a second substrate. This method for manufacturing a wiring board includes: providing a laminated sheet including a carrier, a release layer, and a metal layer, wherein the carrier has a flat region and an uneven region on at least a surface on the metal layer side, and wherein the uneven region is provided in a pattern surrounding the flat region; forming a resin-containing layer on a surface of the metal layer to obtain a carrier-attached first substrate; cutting the carrier-attached first substrate according to the pattern of the uneven region to obtain an individualized carrier-attached first substrate; and laminating the individualized carrier-attached first substrate onto a second substrate so that the carrier is on the outside, to obtain a composite substrate.
1 . A method for manufacturing a wiring board, comprising:
providing a laminated sheet comprising a carrier, a release layer, and a metal layer in order, wherein the carrier has a flat region having a developed interfacial area ratio Sdr of less than 5% as measured in accordance with ISO 25178, and an uneven region having a developed interfacial area ratio Sdr of 5% or more and 39% or less as measured in accordance with ISO 25178, on at least a surface on the metal layer side, and wherein the uneven region is provided in a pattern surrounding the flat region;
forming a resin-containing layer on a surface of the metal layer to obtain a carrier-attached first substrate;
cutting the carrier-attached first substrate according to the pattern of the uneven region to obtain an individualized carrier-attached first substrate; and
laminating the individualized carrier-attached first substrate onto a second substrate so that the carrier is on the outside, to obtain a composite substrate.
2 . The method for manufacturing a wiring board according to claim 1 ,
wherein a width of the pattern of the uneven region in the laminated sheet is more than 1.0 mm, and
wherein the method for manufacturing a wiring board further comprises trimming the individualized carrier-attached first substrate so that the width of the pattern of the uneven region at a periphery of the individualized carrier-attached first substrate is 1.0 mm or less all around, before laminating the individualized carrier-attached first substrate onto the second substrate.
3 . The method for manufacturing a wiring board according to claim 1 , further comprising:
placing the composite substrate on a stage so that the individualized carrier-attached first substrate is on the outside, to make the second substrate adhere to the stage; and
releasing the carrier from the release layer so that the second substrate forms a convex curved surface with a radius of curvature of 200 mm or more and 5000 mm or less, while making the second substrate adhere to the stage.
4 . The method for manufacturing a wiring board according to claim 1 , wherein the carrier-attached first substrate has a thickness of 150 μm or more and 3000 μm or less, and the second substrate has a thickness of 300 μm or more and 3000 μm or less.
5 . The method for manufacturing a wiring board according to claim 1 , wherein the carrier has a plurality of the flat regions, and wherein the uneven region is provided in a linear pattern defining the flat regions.
6 . The method for manufacturing a wiring board according to claim 1 , wherein the carrier is composed of glass, silicon, ceramics, or metal.
7 . The method for manufacturing a wiring board according to claim 1 , wherein the resin-containing layer comprises a wiring layer and an insulating layer.
8 . The method for manufacturing a wiring board according to claim 7 , wherein the insulating layer is composed of an insulating resin.
9 . The method for manufacturing a wiring board according to claim 7 , wherein the forming the resin-containing layer comprises:
forming a first wiring layer on a surface of the metal layer; and
alternately forming an insulating layer and a wiring layer on the surface of the laminated sheet on which the first wiring layer has been formed, to obtain a resin-containing layer in which the first wiring layer is incorporated in a form of an embedded wiring layer.
10 . The method for manufacturing a wiring board according to claim 7 , wherein the resin-containing layer is an interposer.
11 . The method for manufacturing a wiring board according to claim 1 , wherein the second substrate is a build-up substrate.
12 . The method for manufacturing a wiring board according to claim 1 , wherein the second substrate comprises a core layer, and wherein the core layer is composed of at least one selected from the group consisting of epoxy resin, bismaleimide-triazine resin, FR-4, FR-5, cyanate ester, polyphenylene derivative, glass, prepreg material, polyimide, polyamide, liquid crystal polymer, epoxy-based build-up material, polytetrafluoroethylene, ceramics, and metal oxide.
13 . The method for manufacturing a wiring board according to claim 12 , wherein the second substrate comprises a wiring layer and an insulating layer on at least one surface of the core layer.
14 . The method for manufacturing a wiring board according to claim 1 , wherein in the laminated sheet, an outermost surface of the metal layer has a flat shape corresponding to a surface shape of the flat region of the carrier, and an uneven shape corresponding to a surface shape of the uneven region of the carrier.