Fujitsu Corporation

Yoshiyuki Kimura

Atsushi Kikuchi

Yoshihiko Ikemoto

Muneharu Morioka

Makoto Iijima

Preparing a bottom grounding layer eliminates grounding pins, thereby the number of signal pins can be increased in a multilayer board that includes a grounding layer, a signal layer, a power supply layer, a grounding via, a signal via, a power supply via and the like in the insulation material of the multilayer board, the bottom grounding layer being electrically connected to the grounding layer.

Multilayer board and a semiconductor device

A multilayer wiring substrate includes differential signal wires placed within a first insulating layer between a first power-supply plane and a first ground plane; and general signal wires placed within a second insulating layer between a second power-supply plane and a second ground plane. In the multilayer wiring substrate, the differential signal wires are placed in a different plane from a plane having each of the general signal wires so that the different plane includes a first area having the differential signal wires, and a second area having one of the second power-supply plane and the second ground plane. The general signal wires are placed in a vertical direction of the second area in a laminated state so that each of the general signal wires is placed between the second power-supply plane and the second ground plane.

Growing community of inventors

Kawasaki, Japan

Yoshiyuki Kimura