PCB（Printed Circuit Board）

It is a general term for a board or film on which wiring is formed, and is also called a printed circuit board or printed board.

Today, it is used inside most electrical equipment, and electronic parts such as resistors, capacitors and ICs are mounted on the PCB to form a circuit. It is mainly made by pasting insulating material and copper foil together, and removing unnecessary parts by etching while protecting the necessary parts of the copper foil.

Insulating materials used to be made by immersing paper in phenol or epoxy, but nowadays glass-epoxy substrates are becoming the mainstream. Furthermore, recently, many low-loss materials have been developed along with the increase in signal speed, and there are also cases where alumina-based ceramic materials with high thermal conductivity are used for heat dissipation. With the increasing complexity of circuits and the miniaturization of all electronic devices, multi-layer boards, which consist of many layers of insulation and copper foil, are also gaining considerable weight.

Please note that the same PCB is abbreviated as polychlorinated biphenyl, the use of which is restricted as an environmentally hazardous substance.