Browning method for improving interlayer bonding force of printed circuit board

Abstract

The invention discloses a browning method for improving the interlayer bonding force of a printed circuit board and belongs to the technical field of circuit boards. The browning method comprises thefollowing steps S1, of cleaning, putting a copper foil in a cleaning solution I for soaking for 3-5 min, adding a cleaning solution II, continuing soaking for 3-5 min, then sequentially putting the copper foil in hydrogen peroxide and ethanol for soaking for 2-3 min, and then drying the copper foil with nitrogen; S2, presoaking, putting the cleaned copper foil into a presoaking solution, and carrying out ultrasonic oscillation for 3-5 minutes; S3, browning, namely browning the presoaked copper foil in a browning tank in which browning liquid is stored; and S4, washing, putting the browned copper foil into deionized water, washing with the water, and drying with nitrogen. The method is advantaged in that after browning, a sample plate shows good anti-stripping performance, and the strippingstrength is as high as 0.95 Kg / cm; thermal performance test is carried out, respectively six times of tin immersion are carried out, 100 times of cold and hot impact circulation and six times of reflow soldering test on the laminated sample are carried out, that the test sample has no bubbling, layering or plate explosion phenomenon is observed, and the interlayer bonding force is strong.

Description

technical field [0001] The invention relates to the technical field of circuit boards, in particular to a browning method for improving the bonding force between layers of printed circuit boards. Background technique [0002] Printed circuit board (PCB) is a collective name for printed circuits and printed components; it is based on the basic material as an insulating board, through wiring, drilling, hole metallization, electroplating, etching, surface treatment and other processes, on the board Form a conductive pattern and often accompanied by various holes (such as metallized holes, component holes, etc.), as a chassis for welding various electronic components (such as inductors, capacitors, resistors) to achieve electrical connection between various electronic components interconnection. In recent years, printed circuit boards have been widely used as one of the important electronic components in electronic equipment, acting as a support for electronic components and pr...

AI Technical Summary

Problems solved by technology

The invention also provides a method for using the copper block black / browning device to black / brown the copper block, through the stirring device, the liquid inlet pipe and the liquid discharge pipe and the black / brown liquid in the black / brown line potion tank The formed circulation loop keeps the components of the blackening / browning liquid in the container effective, and the liquid inlet pipe and the liquid discharge pipe are equipped with automatic valves to control the blackening / browning time. Using this method, the copper block blackening / browning is uniform and the quality is good , which solves the problem of uneven browning of copper blocks in the past, which causes air bubbles in the subsequent process and leads to scrapping, and the interlayer bonding force is low.

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