Multilayer blind/buried and blind via printed circuit boards (PCBs) are generally manufactured using a "separate board" production method. This means that multiple pressing, drilling, and via plating processes are required to complete the process, making precise positioning crucial.

　　High-precision printed circuits refer to achieving high density through techniques such as fine linewidth/spacing, micro-vias, narrow ring widths (or no ring width), and buried/blind vias. High precision, however, dictates that the "fine, small, narrow, and thin" characteristics inevitably lead to high accuracy requirements. For example, a 0.20mm linewidth requires a production accuracy of 0.16-0.24mm according to regulations, with an error of (0.20 ± 0.04)mm. Similarly, a 0.10mm linewidth has an error of (0.10 ± 0.02)mm. Clearly, the latter offers twice the precision, and this principle is self-evident. Therefore, high-precision requirements will not be discussed separately.

　　The combination of buried, blind, and through-hole vias (multilayer buried/blind via circuit boards) is also an important way to improve the density of printed circuits. Generally, buried and blind vias are tiny holes. Besides increasing the number of traces on the circuit board surface, buried and blind vias use the closest interlayer interconnects, greatly reducing the number of through-holes and the number of isolation pads, thereby increasing the number of effective traces and interlayer interconnects within the board, and improving interconnect density.

　　The issue of interlayer overlap in the manufacturing of multilayer circuit boards with buried and blind vias: By adopting the pin pre-positioning system used in ordinary multilayer circuit board production, the pattern fabrication of each layer is unified into a single positioning system, creating conditions for successful manufacturing. For ultra-thick single sheets used in this case, such as those with a thickness of 2 mm, a certain thickness layer can be milled away at the positioning hole location, which is also included in the processing capabilities of the four-slot positioning hole punching equipment of the pre-positioning system.