Multi-layer substrate, printed circuit board, a semiconductor package substrate, a semiconductor package, a semiconductor chip, a semiconductor device, an information processing apparatus and a communication device

摘要

PROBLEM TO BE SOLVED: To provide a multilayer substrate capable of suppressing rising of a cost by making a conductor loss for a differential component smaller than a conductor loss for a common component, so that the differential loss is reduced to attenuate common noise.SOLUTION: A multilayer substrate includes a plurality of signal wirings for transferring a differential signal. The plurality of signal wirings include a wiring layer for constituting a pair wiring, a GND layer which faces the wiring layer and contains a GND plane of entire surface or partial one, and a dielectric layer provided between the wiring layer and the GND layer. A wiring width between the plurality of signal wirings is narrower than a wiring width in a case where a characteristic impedance for a single signal wiring is a half of the differential impedance of the pair wiring, and a resistance increase generated by a skin effect on a surface of the plurality of signal wirings is smaller than a resistance increase generated by skin effect on a surface of the GND layer.