To produce a multi-layer PCB, alternating layers of epoxy-infused fiberglass sheet called prepreg and conductive core materials are laminated together under high temperature and pressure using a hydraulic press. The pressure and heat causes the prepreg to melt and join the layers together.

What is multilayer PCBs?

Multilayer PCB is a circuit board that has more than two layers. Unlike a Double-Sided PCB which only has two conductive layers of material, all multilayer PCBs must have at least three layers of conductive material which are buried in the center of the material.

How PCB are manufactured?

The manufacture of the PCBs is normally achieved using a chemical etching process. ... Typically the copper on the bare printed circuit boards is covered with a thin layer of photo-resist. It is then exposed to light through a photographic film or photo-mask detailing the tracks required.