[Image] Click on the “blue text” to follow us. Introduction With the continuous development of printed circuit board technology, the number of layers, density (especially the density of small pads on inner and outer layers), and the increase in panel area, along with the complexity of structures (coexistence of buried, blind, and through-hole structures), the requirements for interlayer alignment in multilayer boards are becoming increasingly stringent. Currently, the requirements for dimensional stability in printed circuit boards have reached a precision of no more than 1 mil variation per 24 inches, …