Provided is a photosensitive resin composition containing: a photopolymerizable compound (A) having an ethylenically unsaturated group; a photopolymerization initiator (B); and an inorganic filler (F), in which the photopolymerizable compound (A) having an ethylenically unsaturated group includes a photopolymerizable compound (A1) having an acidic substituent and an alicyclic structure together with an ethylenically unsaturated group, and the inorganic filler (F) includes an inorganic filler surface-treated with a coupling agent without at least one functional group selected from the group consisting of an amino group and a (meth)acryloyl group. The present disclosure also provides a photosensitive resin composition for photo via formation, and a photosensitive resin composition for interlayer insulating layer. The present disclosure further provides: a photosensitive resin film and a photosensitive resin film for interlayer insulating layer, each of which contains the photosensitive resin composition; a multilayered printed wiring board and a semiconductor package; and a method for producing a multilayered printed wiring board.

A method for manufacturing a circuit board includes providing an insulating substrate, defining a through hole in the insulating substrate, forming a first conductive layer on two surfaces of the insulating substrate and on an inner wall of the through hole, forming a phase change material layer on a surface of each first conductive layer, forming a seed layer on a surface of the first conductive layer, forming a second conductive layer on a surface of the seed layer, and etching the seed layer, the first conductive layer, and the second conductive layer, so that a first conductive circuit layer and a second conductive circuit layer are respectively formed on two opposite surfaces of the insulating substrate, so that the phase change material layer is embedded in the first conductive circuit layer and in the second conductive circuit layer. The application also provides a circuit board.

This tin or tin alloy electroplating solution according to one aspect contains a soluble salt (A) including at least a stannous salt, one or more compounds (B) selected from the group consisting of an organic acid, an inorganic acid, and a salt thereof, a surfactant (C) that is a polyoxyethylene polycyclic phenyl ether sulfuric acid ester salt represented by the following General Formula (1), and a leveling agent (D).

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In General Formula (1), m is an integer of 1 to 3, n is an integer of 10 to 30, and X is a cation.

A printed circuit board may include a substrate body portion, conductive patterns on a top surface of the substrate body portion, and a photosensitive insulating layer on the top surface of the substrate body portion and including an opening exposing at least one of the conductive patterns. The photosensitive insulating layer includes first to third sub-layers stacked sequentially. The first sub-layer includes an amine compound or an amide compound A refractive index of the second sub-layer is lower than a refractive index of the third sub-layer. A photosensitizer content of the second sub-layer is higher than a photosensitizer content of the third sub-layer.

A printed circuit board includes a first insulating layer having a through hole, and a via disposed to fill the through hole and to be extended to at least one surface of the first insulating layer, wherein the via includes a plating layer having an inner wall part disposed on an inner wall of the through hole and a land part extended from the inner wall part and disposed on the at least one surface of the first insulating layer, and a metal paste layer including metal particles, and filled in the rest of the through hole and disposed on the plating layer.

A substrate for a printed circuit board according to an embodiment of the present invention includes a base film having insulating properties and a sintered layer formed of a plurality of metal particles, the sintered layer being stacked on at least one surface of the base film, in which a region of the sintered layer extending from an interface between the sintered layer and the base film to a position 500 nm or less from the interface has a porosity of 1% or more and 50% or less.

A method of producing a wired circuit board including an insulating layer and a conductive pattern, including: (1), an insulating layer having an inclination face, (2), a metal thin film provided at least on the inclination face, (3), a photoresist provided on the surface of the metal thin film, (4), a light shield portion of a photomask disposed so that a first portion, where the conductive pattern is to be provided in the photoresist, is shielded from light, and the photoresist is exposed to light through the photomask, (5), the first portion of the photoresist is removed to expose the metal thin film corresponding to the first portion, and (6), the conductive pattern is provided on the surface of the metal thin film exposed from the photoresist.

A method for producing a wiring circuit board includes first forming a base insulating layer, and second forming a first wiring and a second wiring having different thicknesses from each other in order. The second step includes, in order, forming a seed film, forming a first resist in a reversed pattern of the first wiring on one surface in a thickness direction of the seed film, forming the first wiring on one surface in the thickness direction of the seed film by plating, removing the first resist, of forming a second resist in a reversed pattern of the second wiring on one surface in the thickness direction of the seed film to cover the first wiring, forming the second wiring on one surface in the thickness direction of the seed film by plating, removing the second resist, and removing the seed film.

A wiring board includes a wiring layer, an insulating layer, a plurality of opening portions, and a connection terminal. The insulating layer is laminated on the wiring layer and covers a wiring pattern. Each of the plurality of opening portions penetrates through the insulating layer to the wiring pattern. The connection terminal is formed on the respective opening portions and comes into contact with the upper surface of the wiring pattern. The wiring layer includes a first wiring pattern, and a second wiring pattern that is formed of a plurality of laminated metal layers and that is thicker than the first wiring pattern. An upper surface of a metal layer serving as an uppermost layer of the second wiring pattern is a contact surface with the connection terminal and has a same width as an upper surface of a metal layer serving as a layer other than the uppermost layer.

A wiring board includes: a substrate having transparency; a plurality of first wirings which are arranged on an upper surface of the substrate and extend in a first direction and each of which has a back surface in contact with the substrate and a front surface facing an opposite side of the back surface; and has a back surface in contact with the substrate and a front surface facing an opposite side of the back surface. The first wiring has a pair of side surfaces which extend in the first direction and are adjacent to the back surface of the first wiring, and each of the pair of side surfaces of the second wiring is recessed inward. The second wiring has a pair of side surfaces which extend in the second direction and are adjacent to the back surface of the second wiring.