A wiring board according to the present disclosure has at least a structure in which a wiring conductor layer is layered on a surface of an insulating layer containing particles of silica, and some particles of silica among the particles of silica contained in the insulating layer are partially exposed on the surface of the insulating layer. The wiring conductor layer includes a seed layer in contact with the insulating layer and a plated conductor layer formed on a surface of the seed layer. At a contact surface between the exposed portions of the particles of silica and the seed layer, an amorphous layer of silica derived from the particles of silica and an amorphous layer of metal derived from metal forming the seed layer are present.

A wiring substrate includes an insulating layer including inorganic fillers and resin, and a conductor layer formed on a surface of the insulating layer and having a conductor pattern. The surface of the insulating layer has an arithmetic average roughness Ra in the range of 0.05 μm to 0.5 μm, the conductor layer includes a metal film formed on the surface of the insulating layer, and the inorganic fillers include a first inorganic filler including particles such that each of the particles has a portion of a surface separated from the resin and forming a gap with respect to the resin of the insulating layer and that the metal film of the conductor layer includes part formed in the gap between the first inorganic filler and the resin.

A component carrier includes an electrically insulating layer structure with a first main surface and a second main surface, a through hole extends through the electrically insulating layer structure between the first main surface and the second main surface. The through hole has a first tapering portion extending from the first main surface and a second tapering portion extending from the second main surface. The through hole is delimited by a first plating structure on at least part of the sidewalls of the electrically insulating layer structure and a second plating structure formed separately from and arranged on the first plating structure. The second plating structure includes an electrically conductive bridge structure connecting the opposing sidewalls.

A wiring circuit board sequentially includes a conductive layer, an insulating layer, and a shield layer toward one side in a thickness direction. The insulating layer covers the conductive layer and has an insulating opening portion exposing a part of a one-side surface in the thickness direction of the conductive layer, and the shield layer has a recessed portion disposed at the inside of the insulating opening portion and recessed toward the other side in the thickness direction so as to be in contact with the conductive layer. The shield layer sequentially includes an adhesive layer and a main body layer toward one side in the thickness direction. A ratio (Tb/Ta) of a thickness Tb of the main body layer to a thickness Ta of the adhesive layer is 4 or more.

A multilayer wiring board that improves the reliability of connection at a via hole connection portion, and a method for producing the multilayer wiring board. In a multilayer wiring board comprising a plurality of metal wiring layers alternately laminated with insulating layers interposed therebetween are electrically connected to each other via a via hole plated layer, wherein a dissimilar metallic layer, made from material different from that of the metal wiring layers, is interposed between each of the metal wiring layers on the bottom surface of the via hole and the via hole plated layer, and the dissimilar metallic layer interposed between the each of the metal wiring layers on the bottom surface of the via hole and the via hole plated layer is arranged in a concave shape on the surface of the concave portion formed in the metal wiring layer on the bottom surface of the via hole.

The present invention relates to an etching solution composition for selectively etching only silver, a silver alloy, or a silver compound, and to a circuit forming method using the composition. The circuit forming method according to the present invention is characterized in that, in a substrate material in which an electrically conductive seed layer and a circuit layer are formed of heterogeneous metals, only the seed layer is selectively etched to enable the implementation of fine pitches. In addition, the present invention relates to a circuit forming method and an etching solution composition, wherein only a seed layer of silver (Ag), a silver alloy, or a silver compound is selectively etched without etching a copper (Cu) plated circuit.

A surface finish for a printed circuit board (PCB) and semiconductor wafer includes a nickel disposed over an aluminum or copper conductive metal surface. A barrier layer including all or fractions of a nitrogen-containing molecule is deposited on the surface of the nickel layer to make a barrier layer/electroless nickel (BLEN) surface finish. The barrier layer allows solder to be reflowed over the surface finish. Optionally, gold (e.g., immersion gold) may be coated over the barrier layer to create a nickel/barrier layer/gold (NBG) surface treatment. Presence of the barrier layer causes the surface treatment to be smoother than a conventional electroless nickel/immersion gold (ENIG) surface finish. Presence of the barrier layer causes a subsequently applied solder joint to be stronger and less subject to brittle failure than conventional ENIG.

A printed circuit board includes an insulating body, a wiring structure at least disposed on the insulating body; and a shielding portion including a conductive via disposed around the wiring structure of the insulating body. The conductive via includes first and second metal layers having different degrees of magnetic permeability.

The base material for printed circuit board according to one aspect of the present disclosure is a base material for printed circuit board comprising a base film having an insulating property, a sintering layer inducing a plurality of copper particles and formed on at least one surface of the base film and an electroless copper plating layer formed on a surface of the sintering layer, the surface being on an opposite side to the base film, and filled in the sintering layer, and wherein a lightness L* of a surface of the electroless copper plating layer, the surface being on an opposite side to the sintering layer, is 45.0 or more and 85.0 or less, a chromaticity a* thereof is 5.0 or more and 25.0 or less, and a chromaticity b* thereof is 5.0 or more and 25.0 or less.

A glass wiring board that can be kept from cracking by better preventing concentration of stresses in a glass plate on which a conductor layer including an electrolytic copper plating layer is provided, the wiring board includes: a glass plate; a first metal layer covering at least a part of the glass plate; and a second metal layer covering at least a part of the first metal layer, and the area of the first metal layer in contact with the second metal layer is smaller than the area of the second metal layer facing the first metal layer.