IMPEDANCE CONTROL FILM, IMPEDANCE CONTROL SHIELD FILM, AND WIRING BOARD USING THEM

摘要

PROBLEM TO BE SOLVED: To provide an impedance control shield wiring board or the like which control the characteristic impedance and/or capacitance of signal lines without resorting to the adjustment of the thickness of insulators in the wiring board or of the width of conductors or spaces in wiring. SOLUTION: In the wiring board, the open-area percentage of an opening metal thin film layer 12 is adjusted to vary the counter area of the thin film layer 12 against signal lines 42a to adjust the characteristic impedance and/or capacitance of the signal lines 42a. Thus, the characteristic impedance is set to a desired value and waveforms are prevented from getting dull. In addition, the wiring board is provided with a non-opening metal thin film layer 22, which is connected to a ground potential body via a ground member 7 to shield the signal lines 42a from unnecessary radiation. COPYRIGHT: (C)2006,JPO&NCIPI