Ibiden Company Limited

Masanori Tamaki

Ryo Enomoto

Toru Nakai

Youhong Wu

Yoshimi Matsuno

Masaki Ohno

A multilayered printed wiring board has a core substrate having a through hole opening with a radius R, a through hole structure formed at the through hole opening and including a lid-shaped conductive structure, a first interlaminar resin insulation layer formed over the core substrate and having a first via hole structure with a bottom radius r, and a second interlaminar resin insulation layer formed over the first interlaminar resin insulation layer and having a second via hole structure. The lid-shaped conductive structure is formed over the core substrate at an end portion of the through-hole opening and covering the end portion of the through-hole opening. The first via hole structure is formed on the lid-shaped conductive structure and has an electroless plated film and an electrolytic plated film. The second via hole structure has an electroless plated film and an electrolytic plated film. The first via hole has a gravity center at or beyond a radius D, where D=(R&#x2212;r/3) and the radius D is measured from a gravity center of the through-hole opening, and the bottom radius r of the first via hole is larger than a bottom radius of the second via hole.

Multilayered printed wiring board

A printed wiring board including resin insulation layers, and conductive circuits formed between the resin insulation layers such that spaces between the conductive circuits are filled with a resin material of the resin insulation layers. The conductor circuits include a first conductive circuit and a second conductive circuit positioned adjacent to the first conductive circuit, each of the first and second conductive circuits has a trapezoidal cross section, and the first and the second conductive circuits satisfy a formula, 0.10T&#x2266;|W&#x2212;W|&#x2266;0.73T where Wrepresents a width of a space between upper surfaces of the first and second conductive circuits, Wrepresents a width of a space between lower surfaces of the first and second conductive circuits, and T represents a thickness of each of the first and second conductive circuit.

Printed wiring board and manufacturing method thereof

A printed wiring board having an interlayer insulation layer and conductive circuits formed on the interlayer insulation layer. The conductive circuits include a first conductive circuit and a second conductive circuit positioned adjacent to each other, and the first and second conductive circuits satisfy a formula, 0.10 T&#x2266;|W&#x2212;W|&#x2266;0.73 T, where Wrepresents an upper conductive circuit space between the first and second conductive circuits, Wrepresents a lower conductive circuit space between the first and second conductive circuits, and T represents a thickness of the first and second conductive circuits.

A semiconductor mounting boardis prepared by electrically joining an IC chipvia an interposerof high rigidity to external padsand internal pads, which are formed on the uppermost surface of a build-up layer. When the IC chipgenerates heat, since padsare positioned away from the center, a large shearing stress is applied to the portions at which padsare joined to the interposerin comparison to the portions at which padsare joined to the interposer. Here, padsare formed at substantially flat wiring portions and thus when joined to the interposerby means of solder bumps, voids and angled portions, at which stress tends to concentrate, are not formed in the interiors of solder bumps. The joining reliability is thus high.

Semiconductor mounting board

Each via hole of a printed wiring board is filled with a metal conductor. A distal end of each metal conductor is covered with a diffusing metal layer. The distal end of the metal conductor is pressed against a conductor circuit of another substrate, and the printed wiring boards are bonded together by thermocompression bonding. The metal of the distal end of each metal conductor is diffused into the metal of the conductor circuit so that an alloy layer is formed in an interface. As a result, reliability in the interlayer electrical connection can be improved.

Printed-circuit board, multilayer printed-circuit board and method of manufacture thereof

Printed circuit board having excellent peel strength and conductance resistance is provided with a substrate, a resin insulating layer formed thereon and roughened at its surface, and a conductor formed thereon, in which at least a portion of the conductor is composed of an eutectic metal layer.

Growing community of inventors

Gifu, Japan

Masanori Tamaki