Developing Build-up Printed Wiring Board with 1-3 Layer Via for Notebook PC

Abstract

We have developed and adopted build-up technology for printed wiring boards (PWB) of notebook PC, which uses via holes that connect 3 layers compared to the normal build-up PWB which used via holes that connect 2 layers. This technology is more superior in electrical characteristics, which enables one to easily control characteristic impedance and reduce crosstalk noise. For the method of manufacturing, we selected laser drilling method and B²it^TM. Although the shape of their vias are different, their electrical characteristics are equal.