To provide a printed wiring board suppressing resonance current between a power source layer and a ground layer to suppress electromagnetic radiation caused by the resonance current.
The power source layer 3 and a second insulation substrate layer 7 are formed on one surface of an insulation layer 2 in which a first signal wiring layer 1 is formed and the ground layer 4 and a first insulation substrate layer 5 are formed on the other surface of the layer 2. A second signal wiring layer 6 is formed on the first insulation substrate layer 5 and a third signal wiring layer 8 is formed on the second insulation substrate layer 7. An electromagnetic radiation suppressing member 20 with a thin film layer 10 is formed to cover the entire side faces of the insulation layer 2, the power source layer 3 and the ground layer 4 and to partially cover the surfaces of the power source layer 3 and the ground layer 4. The thin film layer 10, in a frequency domain including a predetermined frequency domain, has a characteristic exhibiting a negative dielectric constant and a positive magnetic permeability.
OTSUKA KANJI
AKIYAMA YUTAKA
| JP2004363347A | 2004-12-24 | |||
| JP2003218541A | 2003-07-31 | |||
| JP2004327687A | 2004-11-18 | |||
| JPH11177273A | 1999-07-02 |
| US20060237223A1 | 2006-10-26 |
Endo Wako
Next Patent: METHOD FOR GRINDING SEMICONDUCTOR WAFER