Three Multilayer PCB manufacturing method has been disclosed.They are gap method (Clearance Hole), added layer method (Build Up), plated through Law (PTH).Since the clearance hole method even in the manufacturing costs of working hours, and the high density is limited, therefore has not been practical.Additional layer method rather complex due to manufacturing methods, coupled with high density, but at the time the demand for higher density is not as urgent now come,so has been an inglorious.Now due to demand for high-density circuit boards and more, once again become the focus of research and development of various manufacturers. As with the double-sided PTH same process of law, is still the mainstream of Multilayer PCB manufacturing method.
Multilayer inner graphic production methods generally do first, and then etching printed to form single-sided or double-sided board .And incorporated between layers specified, then by heat, pressure and be bonded, the drilled and double panel PTH are in the same method .These basic production methods and engineering methods dating back to the 1960s, not much change, but with materials and process technologies (eg: Lamination adhesive technology to produce glue residue, film improved solving drilling) more mature, annexed I Multilayer PCB feature even more diverse.