PCB manufacturing method for preventing green oil plug holes

Abstract

Provided is a PCB (Printed Circuit Board) manufacturing method capable of preventing green oil hole plugging, comprising the steps of: (1) pre-welding treatment; (2) screen printing: forming a layer of solder resist ink on a copper layer; (3) preliminary baking: performing preheating; (4) counterpoint exposure: performing selective ultraviolet exposure on the solder resist ink covering the area needing solder resist to form a solder resist layer; (5) developing; (6) secondary counterpoint exposure: performing secondary ultraviolet exposure on the area except the function hole of a PCB; (7) secondary developing: employing chemical liquid medicine to perform secondary developing on solder resist ink in the function hole so as to thoroughly remove solder resist ink left in the function hole; (8) board checking; (9) postbaking; and (10) performing pre-welding treatment, screen printing, preliminary baking, counterpoint exposure, developing, secondary counterpoint exposure, secondary developing, board checking and postbaking again on the PCB. The method introduces secondary counterpoint exposure and secondary developing, and effectively solves the problem of hole plugging.

Description

Technical field [0001] The invention relates to a PCB board processing technology, in particular to a PCB manufacturing method for preventing green oil plugging holes. Background technique [0002] In the past ten years, the printed circuit board (PCB) manufacturing industry has developed rapidly. The printed circuit board has developed from single-layer to double-sided, multi-layer and flexible boards, and continues to move towards high precision and high Development in the direction of density and high reliability. Continuously shrinking volume, reducing costs, and improving performance have enabled printed circuit boards to maintain strong vitality in the development of future electronic products. In the future, the development trend of printed circuit board manufacturing technology is to develop in the direction of high density, high precision, fine aperture, fine wire, small spacing, high reliability, multilayer, high-speed transmission, light weight, and thinness. [0003] ...

AI Technical Summary

Problems solved by technology

[0003] Due to the continuous development of circuit board manufacturing technology towards high-density interconnection, the hole diameter of the electric hole is getting smaller and smaller, and the minimum hole diameter has been developed from 0.25mm in the past to 0.20mm, and the hole density is increasing. In the circuit board manufacturing process, it is easy to There is a problem of solder resist ink plugging holes, which leads to a series of quality defects, such as functional problems such as over BGA, SMT lack of gold plating, open circuit of via holes, etc.

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