Multilayer Printed Circuit Board is a precision electronic interconnection carrier composed of three or more conductive pattern layers and insulating dielectric layers alternately laminated, with interlayer electrical connection realized through plated holes. Its core structure adopts the "core board + Prepreg" alternate lamination process: first, the inner core board circuit is fabricated, then precisely aligned and laminated with prepreg and outer copper foil, and finally through holes or blind/buried vias are formed by drilling and electroless copper deposition processes to achieve reliable conduction between layers. Compared with single-sided/double-sided boards, Multilayer PCB has become the core foundation for high-end electronic equipment to realize complex functions due to its higher integration, better signal integrity and smaller space occupation.