A method of improving exposure precision of hdi circuit board

Abstract

The invention discloses a method for improving the exposure accuracy of an HDI circuit board, which includes the following steps: a. Drilling a plurality of through-hole alignment holes through mechanical drilling on the non-circuit area of ​​the copper-clad board; b. On the periphery of the hole alignment hole, a blind hole alignment hole group is drilled at the position without copper layer by laser drilling; c. In the exposure process, the film used is provided with a through hole alignment hole and a blind hole alignment hole group The through hole target and the blind hole target corresponding to the bit hole; before exposure, the through hole alignment hole and the through hole target are pre-aligned, and then the blind hole alignment hole group is used to correct the alignment with the corresponding blind hole target. The present invention adopts through hole alignment hole and blind hole alignment hole to carry out alignment at the same time, so that the offset distance of the film is at the median value of the difference between the two alignment hole offsets, so that the blind hole processing position obtained after development and The offset of the pattern of the through-hole processing position will not be too large.

Description

technical field [0001] The invention relates to the technical field of production of HDI circuit boards, in particular to a method for improving the exposure precision of HDI circuit boards. Background technique [0002] HDI is the abbreviation of High Density Interconnectd, and its full name in Chinese is High Density Interconnect Circuit Board, which connects any layer of circuits to each other through blind holes, buried holes, and through holes. The processing method generally includes (1) pre-treatment such as cleaning and roughening of the copper clad laminate as the inner core board; (2) forming lines on each inner core board: (3) combining the inner core board with the sub-inner layer (4) Making buried holes; (5) Forming lines on the sub-outer board; (6) Laminating the outer copper-clad board; (7) Drilling blind holes by laser drilling; (7) Using Make through holes by mechanical method; (8) Make outer circuit. When making the circuit of the inner core board, the se...

AI Technical Summary

Problems solved by technology

Using the existing alignment holes and alignment targets for film alignment, the blind hole window pattern on the film will be offset based on the through-hole alignment hole

In the early follow-up blind hole processing process, because the degree of expansion and contraction of the copper clad laminate is different from that of the through hole processing, the processed blind hole will deviate from the blind hole processing position, resulting in the deformation of the formed circuit and affecting the circuit board product. Performance

Especially in the production of products with fine and dense lines, the insulating material of the non-blind hole processing position is removed due to deviation, which will cause irreversible damage to the adjacent layers of the product due to short circuit

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