printed circuit boards (PCBs) are made of non-conductive substrates coated in conductive laminate copper sheets. The substrates used in PCB are mainly divided into two categories: organic substrates and inorganic substrates. Among them, the organic substrates are made of several types of materials which refer to the reinforcing materials, such as glass fiber cloth, fiber paper, glass felt, etc. These reinforcing materials are impregnated with resin adhesive and dried, then covered with copper foil at high temperature and high pressure. This type of substrate, known as copper clad laminate (CCL), is the main material used to make PCB.
Because of the complex systems PCBs ultimately manage and serve, they have to be carefully built and tested. Part of this process includes the manufacture of a PCB prototype—a model that can be tested as a stand-in for the eventual product—that is used to look for design, mechanical, and electrical flaws. Although PCB prototypes are used in testing, there are differences in the way they are manufactured, the purposes they serve, and the materials used.