High-precision circuit board electrotinning method

Abstract

The invention discloses a high-precision circuit board electrotinning method. A circuit board comprises micro blind holes or micro through holes. An electrotinning process comprises a pretreatment procedure, an electrotinning procedure and an aftertreatment procedure. A strong and uniform stirring function is achieved on a plating solution through ultrasonic waves in the electroplating process, the surface of a material can keep clean all the time through the function, the tin ion discharge process is uniform and stable, and therefore the uniformity and smoothness of plating are improved; the binding force of the plating is increased through ultrasonic strengthening electroplating, and due to the fact that the surface of the plating keeps clean all the time through the strong and uniform stirring function of the ultrasonic waves, the binding force of the plating is increased; and an additive is adopted, an anionic surfactant of sodium salt of a sulfosuccinate group and oxygen vinyl serves as a dispersing agent, and therefore the comprehensive electroplating performance of an electrotinning solution is remarkably improved, the electrotinning solution has high dispersing performance and excellent ductility, and the quality of the plating is further improved.

Description

technical field [0001] The invention relates to the technical field of circuit board production, in particular to a high-precision circuit board electro-tinning method. Background technique [0002] With the rapid development of electronic technology, whether it is military supplies or circuit boards for communication, circuit boards are developing towards miniaturization and integration. However, circuit boards are increasingly required to have smaller apertures and higher layers and board thicknesses, resulting in an increasingly urgent need for high-aspect-ratio processes. The industry's tests and measures on PCB deep-hole copper plating are relatively mature, but there are not many studies on the anti-corrosion performance of tin plating. In the process of PCB deep-hole processing, the anti-corrosion performance of tin plating is facing a severe test. How to effectively improve the corrosion resistance of the coating, reduce the proportion of copper-free scrap in the ho...

AI Technical Summary

Problems solved by technology

In the case of over-drawing, often due to the presence of air in the PCB hole, the wettability of the liquid medicine is not enough, resulting in poor tin plating, no copper in the hole and other poor plating defects, exceeding IPC acceptance standards or customer standards, seriously affecting quality problems