A method for detecting the alignment degree of exposure on both sides of inner substrate of circuit board

Abstract

The invention provides a method for detecting the exposure alignment of two sides of an inner-layer substrate of a circuit board. The method comprises the following steps: step 202, setting a first marker, wherein the first marker is positioned on the upper surface of the inner-layer substrate of the circuit board and comprises a plurality of first grids with equal side lengths; step 204, setting a second marker, wherein the second marker is positioned on the lower surface of the inner-layer substrate of the circuit board, corresponds to the first marker and comprises a plurality of second grids corresponding to the first grids respectively, and the side lengths of the plurality of second grids are gradually reduced and are smaller than those of the first grids; step 206, performing two-side exposure, graphic development and etching on the inner-layer substrate of the circuit board; and step 208, comparing the relative positions of the first grids and the second grids, and judging the offset direction and the offset size. By adopting the technical scheme, the exposure offset direction and offset size of the inner-layer substrate of the circuit board can be quickly detected by a worker, and the production efficiency can be improved.

Description

technical field [0001] The invention relates to the field of production and manufacture of inner substrates of circuit boards, and more specifically relates to a method for detecting the exposure alignment of both sides of inner substrates of circuit boards. Background technique [0002] In the PCB (printed circuit board) production process, the commonly used exposure process includes three parts: inner and outer circuit production and solder resist paint production. The process steps are all to carry out photosensitive film pressing or coating photosensitive emulsion first, and then carry out processes such as exposure and development. In the process of PCB pattern transfer exposure operation, the accuracy of exposure alignment is a key factor in the process capability. In the production process, due to factors such as tools used, plate size differences, system design logic changes, and exposure equipment, etc., the exposure alignment accuracy will be directly affected. Th...

AI Technical Summary

Problems solved by technology

[0004] The existing method of checking the exposure alignment of both sides of the inner substrate of the circuit board can only judge whether the alignment of the graphics on both sides is within the specified range, and it is not conducive for the staff to find the PCB exposure offset in time when the alignment offset is large. cause, thereby affecting production efficiency

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