WIRING BOARD WITH REDUCED CROSSTALK NOISE BETWEEN SIGNAL LINES AND ITS MANUFACTURE

摘要

PURPOSE:To reduce crosstalk and to make the characteristic impedance unchanged by arranging a dielectric of a specific dielectric constant lower than a specific constant of the dielectric substance for a dielectric board between signal wire conductors on one side of the dielectric board. CONSTITUTION:A ground layer 1 is formed to one side of a dielectric board and wiring conductors 2 being signal wires are formed on other side of the said board to constitute a wiring board. A 2nd dielectric substance 4 with a lower specific dielectric constant than a specific dielectric constant of a 1st dielectric substance 3 forming the major part of the dielectric board is arranged between the conductors 2 formed on the dielectric board. Thus, the crosstalk with the adjacent conductors 2 is reduced. Since the insulator placed between the conductor 2 and the layer 1 with the width of the conductor wire has a constant dielectric constant, the characteristic impedance is unchanged.