The names of circuit boards include: Ceramic circuit board, alumina ceramic circuit board, aluminum nitride ceramic circuit board, circuit board, PCB board, aluminum substrate, high-frequency board, thick copper plate, impedance board, PCB, ultra-thin circuit board, ultra-thin circuit board, printed (copper etching technology) circuit board, etc. Circuit boards play an important role in miniaturizing and visualizing circuits, as well as optimizing the layout of electrical appliances for mass production of fixed circuits. A circuit board can be called a printed circuit board or a printed circuit board, with English names such as (Printed Circuit Board) PCB, (Flexible Printed Circuit Board) FPC circuit board (FPC circuit board, also known as flexible circuit board). FPC circuit board is a highly reliable and excellent flexible printed circuit board made of polyimide or polyester film as the substrate. It has the characteristics of high wiring density, light weight, thin thickness, and good flexibility. It is also known as a flexible and hard combination plate. The birth and development of FPC and PCB have given rise to the new product of flexible and hard combination plate. Therefore, the combination of soft and hard circuit boards refers to the combination of flexible circuit boards and rigid circuit boards through pressing and other processes according to relevant process requirements, forming a circuit board with FPC characteristics and PCB characteristics.