Fujitsu Corporation

Shinko Electric Industries Co., Ltd.

Hideaki Yoshimura

Kenji Iida

Yasutomo Maehara

Takashi Nakagawa

Tomoyuki Abe

Shin Hirano

Kenji Fukuzono

Norikazu Ozaki

Seigo Yamawaki

Kishio Yokouchi

Katsuya Fukase

Takashi Kanda

Hitoshi Suzuki

Shunichi Kikuchi

Yasuhito Takahashi

Minoru Hirano

Kiyotaka Seyama

Hitoshi Nori

Kei Fukui

Tomohisa Yagi

Kazuya Arai

Shinpei Ikegami

Hnin Nway San Nang

Asami Hondo

A method of manufacturing a wiring board includes: forming an outer through hole in a core substrate; filling the outer through hole with an insulation resin; forming a first conductive layer on a surface of the insulation resin at a portion where a core connecting via is formed; forming a land around the first conductive layer; laminating the wiring layer on the core substrate after the forming of the first conductive layer and the forming of the land; forming an inner through hole having a smaller diameter than that of the outer through hole and penetrating through the core substrate and the wiring layer so as to penetrate through the insulation resin; and coating a first conductive film on an inner wall surface of the inner through hole, in which the core substrate and the first conductive film are electrically connected through the first conductive layer and the land.

Method of manufacturing a wiring board having via structures

A wiring substrate includes: a plate-like base material containing carbon fibers; a wiring layer formed on a surface of the base material; a first via including a first through hole penetrating through the base material, a first resin layer formed on an inner wall of the first through hole and including a second through hole, and a first conductive layer formed on an inner wall of the second through hole; and a second via including a third through hole penetrating through the base material and a second conductive layer formed on an inner wall of the third through hole, wherein an inside diameter of the third through hole is greater than an inside diameter of the second through hole.

Wiring substrate and manufacturing method for wiring substrate

A semiconductor chip mounting layer of a package substrate unit includes an insulation layer, a conductive seed metal layer formed on the top surface of the insulation layer, conductive pads formed on the top surface of the conductive seed metal layer, metal posts formed substantially in the central portion on the top surface of the conductive pads, and a solder resist layer that is formed to surround the conductive pads and the metal posts.

Package substrate unit and method for manufacturing package substrate unit

A printed circuit board includes a cell portion which includes cells having a plurality of through bores are arranged in a base material; and a base material portion which exists around an outer edge of the cell portion. The base material is formed of a prepreg, the prepreg includes a fiber material in which fiber threads are oriented in a first direction and in a second direction which is perpendicular to the first direction, and a resin material in which the fiber material is impregnated. The through bores are arranged along a third direction between the first direction and the second direction, wherein one side of the outer edges of the cell extends along the third direction.

Printed circuit board incorporating fibers

A laminated circuit board includes a first wiring board that has a first land formed on a surface thereof; a second wiring board that has a second land formed on a surface thereof; a bonding layer that is laid between the first wiring board and the second wiring board and electrically connects the first land and the second land via a conducting material; and a plate that has a through-hole through which the first land is connected to the second land, wherein a diameter of the through-hole of the plate is larger than a diameter of a component that is made by filling the conducting material.

Laminated circuit board and board producing method

A laminated circuit board includes a first wiring board that has a first land formed on a surface thereof; a second wiring board that has a second land formed on a surface thereof; a bonding layer that is made of a bonding resin, being laid between the first wiring board and the second wiring board, wherein the bonding layer electrically connects the first land and the second land via a conducting material; and a plate that has a through-hole into which the conducting material is supplied, wherein the plate has a resin accommodating space that accommodates therein an excess bonding resin that appears during layer stacking.

A circuit board has plated through holes which are laid out with a fine pitch and meets requirements relating to characteristics such as strength and thermal expansion coefficient. A method of manufacturing a circuit board includes: a step of forming a core portion by thermal compression bonding prepregs formed by disposing carbon fibers so as to produce openings at positions where plated through holes will pass through and impregnating the carbon fibers with resin; a step of forming through holes that pass inside the openings at positions of the openings in the core portion; and a step of forming a conductive layer on inner surfaces of the through holes to form plated through holes at positions that do not interfere with the carbon fibers and thereby produce a core substrate.

Circuit board and method of manufacturing the same

The method of producing a substrate comprises the steps of: forming a through-hole in a base member; filling the through-hole with an insulating material; performing electroless plating to coat the surface of the base member, in which the through-hole has been filled with the insulating material, with an electroless-plated layer; applying photo resist on the electroless-plated layer formed on the surface of the base member; optically exposing and developing the photo resist so as to form a resist pattern coating an end face of the through-hole filled with the insulating material; etching an electrically conductive layer formed on the surface of the base member with using the resist pattern as a mask; and removing the resist pattern coating the end face of the through-hole from the base member with using the electroless-plated layer as a release layer.

Method of producing substrate

A circuit board has plated through holes which are laid out with a fine pitch and meets requirements relating to characteristics such as the thermal expansion coefficient of the circuit board. A method of manufacturing a circuit board includes: a step of forming a core portion by thermal compression bonding prepregs which include first fibers that conduct electricity and second fibers that do not conduct electricity, which have the second fibers disposed at positions where plated through holes will pass through, and which are impregnated with resin; a step of forming through holes at positions in the core portion where the second fibers are disposed; and a step of forming a conductive layer on inner surfaces of the through holes to form plated through holes at positions that do not interfere with the first fibers and thereby produce a core substrate.

The circuit board is capable of tightly bonding a cable layer on a base member even if thermal expansion coefficients of the base member and the cable layer are significantly different. The circuit board comprises: the base member; and the cable layer being laminated on the base member with anchor patterns, which are electrically conductive layers formed on a surface of the base member.

Circuit board and method of producing the same

The first support body is pressed against the second support body in response to the softening of the adhesive sheet. The fillers are allowed to reliably contact with one another between the first electrically-conductive land and the second electrically-conductive land. The fillers melt after the adhesive sheet has been softened. The intermetallic compounds are formed between the fillers and the electrically-conductive lands and between the fillers. Electrical connection is in this manner established between the first electrically-conductive land and the second electrically-conductive land. The matrix material and the adhesive sheet are then cured. The first support body and the second support body are firmly bonded to each other.

Method of making printed wiring board and method of making printed circuit board unit

The method of producing a substrate comprises the steps of: forming a through-hole in a base member; plating the base member so as to coat an inner face of the through-hole with a plated layer; applying photo resist on the base member; optically exposing and developing the photo resist so as to form a resist pattern, which coats at least a planar area of the through-hole; and etching an electrically conductive layer formed on the surface of the base member. The resist pattern is formed so as to separate an area of exposing the conductive layer a prescribed distance away from an edge of the through-hole, and the prescribed length is longer than a distance of etching a side face of the conductive layer in the etching step.

A circuit board has a low thermal expansion coefficient that suits the thermal expansion coefficient of an element to be mounted thereupon and can prevent the occurrence of delamination and cracking of a core layer when the circuit board is used in a low temperature environment. The circuit board is constructed by laminating a core layer and at least one wiring layer, where the at least one wiring layer has slightly smaller external dimensions in a planar direction than the core layer.

Circuit board

The core layer of a core substrate is made of carbon fibers impregnated with resin. When the temperature of the core layer increases, the core layer suffers from an increase in the thickness because of thermal expansion of the resin. The core layer is sandwiched between the insulating layers containing glass fibers. The insulating layers serve to suppress an increase in the thickness of the core layer resulting from the thermal expansion of the core layer. Thermal stress is suppressed in the core substrate.

Core substrate and printed wiring board

Large-sized through holes are formed in a core layer of a printed wiring board. Large-sized vias are formed in the shape of a cylinder along the inward wall surfaces of the large-sized through holes located within a specific area. A filling material fills the inner space of the large-sized via. A small-sized through hole penetrates through the corresponding filling material along the longitudinal axis of the small-sized through hole. A small-sized via is formed in the shape of a cylinder along the inward wall surface of the small-sized through hole. The filling material and the core layer are uniformly distributed within the specific area in the in-plane direction of the core substrate. This results in suppression of uneven distribution of thermal stress in the core layer in the in-plane direction of the core layer.

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Kawasaki, Japan

Hideaki Yoshimura