There are 2 types of printed circuit boards for PCB circuit boards, one with non-metallic edges and the other with metalized edges. In the past, there was not much demand for PCBs with metal edges, and now there are more customer demands. Higher-quality printed circuit board metal edges have attracted more attention because it enhances the functionality of several products that use these printed circuit boards.

With the miniaturization and high-speed operation of circuits, the timing and signal integrity of digital signals have become prominent issues. In addition, due to the integrity of the power supply, the medium and high speed digital signals in the system will cause electromagnetic interference and electromagnetic compatibility problems. High-speed digital signals will not only cause serious interference inside the system, but also radiate to the outside of the system, causing the equipment to exceed the safety limit standards. The side-board radiation of a multilayer PCB is a relatively common source of electromagnetic radiation.

The current-carrying power layer and ground layer will generate electromagnetic radiation at its edges. Due to insufficient power supply bypass, most of the noise comes from stray currents in the power and ground planes. At high frequencies, vias act as stubs and may have high inductance. This kind of through hole can radiate the magnetic field between the layers of the circuit board, and finally gather at the edge.

The PCB board metallization edge process uses metal to surround the entire board edge. This will short-circuit the high-frequency signals reaching the edge of the circuit board and prevent them from radiating. Although this improves the performance of the circuit board, the edge metallization process increases the cost of the printed circuit board.