Forming, in a printed-wiring board, a via sufficiently filled without residual smear, for use in an insulating layer and the size of the via to be formed. A via of a printed-wiring board comprises a first filling portion which fills at least a center portion of a hole, and a second filling portion which fills a region of the hole that is not filled with the first filling portion. An interface which exists between the second and first filling portions, or an interface which exists between the second filling portion and an insulating layer and the first filling portion has the shape of a truncated cone comprising a tapered surface which is inclined to become thinner from a first surface toward a second surface, and an upper base surface which is positioned in parallel to the second surface and closer to the first surface than to the second surface.

The present disclosure provides a printed circuit board and a wire arrangement method thereof. The printed circuit board includes a packaged chip and at least two connectors, wires of the packaged chip that are connected to different connectors are distributed on different board layers; and when the packaged chip is connected to one of the connectors, a via is backdrilled to form a high-speed path from the packaged chip to the connector, and copper walls of board layers corresponding to other connectors are drilled out. The wires of the packaged chip that are connected to different connectors are distributed on different board layers. When the packaged chip is connected to one of the connectors, according to backdrilling of different depths, the via is backdrilled to form a high-speed path from the packaged chip to the connector, and copper walls of board layers corresponding to other connectors are drilled out.

A resin multilayer board includes an insulating substrate including a first main surface and mounting electrodes only on the first main surface. The insulating substrate includes first and second resin layers that are laminated. The Young's modulus of the second resin layers is higher than that of the first resin layers. The first and second resin layers are arranged in a distributed manner along a lamination direction of the first and second resin layers. The insulating substrate includes a first and second portions that are two equally divided portions of the insulating substrate in the lamination direction and are respectively positioned closer to the first main surface and farther from the first main surface, and a volume ratio of the second resin layers in the first portion is higher than a volume ratio of the second resin layers in the second portion.

A printed wiring board includes a laminate, a wiring layer formed on first main surface of the laminate and including conductor pads, via conductors including first and second via conductors and formed in the laminate such that each via conductor has diameter gradually reducing from the first main surface toward second main surface of the laminate, and conductor post formed on the first via conductors such that each conductor post includes a metal foil and a plating layer formed on the metal foil. The via conductors are formed such that the first via conductors are positioned in an outer edge portion of the laminate and have minimum-diameter-side surfaces positioned to form a same plane with the second main surface of the laminate and that the second via conductors are positioned in a central portion of the laminate and have minimum-diameter-side surfaces recessed from the second main surface of the laminate.

In a conventional electronic device and a method of manufacturing the same, reduction in cost of the electronic device is hindered because resin used in an interconnect layer on the solder ball side is limited. The electronic device includes an interconnect layer (a first interconnect layer) and an interconnect layer (a second interconnect layer). The second interconnect layer is formed on the undersurface of the first interconnect layer. The second interconnect layer is larger in area seen from the top than the first interconnect layer and is extended to the outside from the first interconnect layer.

A fibrillated liquid crystal polymer powder containing fibrillated liquid crystal polymer particles. A paste containing a dispersion medium and the fibrillated liquid crystal polymer powder. A method of producing the fibrillated liquid crystal polymer powder. A resin multilayer substrate obtained by laminating a plurality of resin sheets including at least one layer of a liquid crystal polymer sheet. On a surface of at least one layer of the liquid crystal polymer sheet, a thickness adjustment layer made of a fibrillated liquid crystal polymer powder containing fibrillated liquid crystal polymer particles is provided in a region insufficient in thickness when at least the plurality of resin sheets are laminated.

Forming, in a printed-wiring board, a via sufficiently filled without residual smear, for use in an insulating layer and the size of the via to be formed. A via of a printed-wiring board comprises a first filling portion which fills at least a center portion of a hole, and a second filling portion which fills a region of the hole that is not filled with the first filling portion. An interface which exists between the second and first filling portions, or an interface which exists between the second filling portion and an insulating layer and the first filling portion has the shape of a truncated cone comprising a tapered surface which is inclined to become thinner from a first surface toward a second surface, and an upper base surface which is positioned in parallel to the second surface and closer to the first surface than to the second surface.

A resin multilayer board includes an insulating substrate including a first main surface and mounting electrodes only on the first main surface. The insulating substrate includes first and second resin layers that are laminated. The Young's modulus of the second resin layers is higher than that of the first resin layers. The first and second resin layers are arranged in a distributed manner along a lamination direction of the first and second resin layers. The insulating substrate includes a first and second portions that are two equally divided portions of the insulating substrate in the lamination direction and are respectively positioned closer to the first main surface and farther from the first main surface, and a volume ratio of the second resin layers in the first portion is higher than a volume ratio of the second resin layers in the second portion.

In a conventional electronic device and a method of manufacturing the same, reduction in cost of the electronic device is hindered because resin used in an interconnect layer on the solder ball side is limited. The electronic device includes an interconnect layer (a first interconnect layer) and an interconnect layer (a second interconnect layer). The second interconnect layer is formed on the undersurface of the first interconnect layer. The second interconnect layer is larger in area seen from the top than the first interconnect layer and is extended to the outside from the first interconnect layer.

A resin multilayer substrate includes a first resin layer including a thermoplastic resin as a main material, a second resin layer including the thermoplastic resin as a main material and superposed on the first resin layer, a first interlayer-connection conductor passing through the first resin layer in a thickness direction, and a first conductor pattern at an area including a region in which the first interlayer-connection conductor is exposed at the surface of the first resin layer between the first resin layer and the second resin layer. The first conductor pattern includes a portion in or at which a portion of the first interlayer-connection conductor is disposed. The first conductor pattern includes a first portion covering the region exposed at the surface of the first resin layer; and a second portion disposed surrounding the first portion. The first portion and the second portion have different thicknesses from each other.