PCB multi -layer board refers to the multi -layer line board used in electrical products. The multi -layer board uses more single -panel or double panel wiring board. Use one double -sided as the inner layer, two -sided single -sided as the outer layer or two double -sides as the inner layer, two -sided single -sided outer layer printing line board, alternate the positioning system and insulating bonding material, and the electrophoretic graphics The interconnected printing circuit boards are made according to design requirements.

　　With the continuous development of SMT (surface installation technology) and the continuous launch of the new generation of SMD (surface installation device), such as QFP, QFN, CSP, BGA (especially MBGA), make electronic products more intelligent and miniaturized, so Promote major reforms and progress of PCB industry technology. Since IBM first successfully developed high -density and multi -layer boards (SLC) in 1991, major groups from various countries have successively developed a variety of high -density interconnection (HDI) micropores. The rapid development of these processing technologies has prompted the design of PCB to develop in the direction of multi -layer and high -density wiring. The multi -layer printing board is widely used in the manufacturing of electronic products with its flexible, stable and reliable electrical performance and superior economic performance.