STRIP LINE DEVICE, PRINTED WIRING BOARD MOUNTING MEMBER, CIRCUIT BOARD, SEMICONDUCTOR PACKAGE, AND METHOD OF FORMING SAME

摘要

To suppress electromagnetic waves leaking through a power distribution circuit provided on a printed wiring board or a semiconductor package, and to prevent a degradation of a waveform of a signal excited by a high-speed digital circuit. A metal 10 is provided which has a dielectric coating 20 on its surfaces and is shaped like a long plate with a valve action, and the valve metal is coated with a layer 30 of a conductive material via the dielectric coating 20 , so that a characteristic impedance viewed from an input terminal can be reduced over a wide band.