Solder mask pre-treatment process

Abstract

The invention relates to a resistance welding pre-treatment process, which comprises the following steps: S1, grinding a board to be treated; S2, extruding a copper surface to form multiple inverted conical depressions on the copper surface; S3, spray-washing and scouring the copper surface on a substrate with clean water to remove the impurities on the copper surface and wet the copper surface; S3, pickling the copper surface with pickling solution to remove the chemical impurities on the copper surface and slightly micro-etch the copper surface; S4, washing the copper surface with water to remove the residual pickling solution on the copper surface; S5, coarsening the copper surface with coarsening solution; S6, washing the copper surface with water to remove the residual coarsening solution on the copper surface; S7, micro-etching the copper surface with micro-etching solution to further increase the roughness of the copper surface; S8, washing the copper surface with water to remove the residual micro-etching solution on the copper surface; and S9, using an absorbent material to absorb the moisture on the board to be treated and drying the board to be treated. By using the resistance welding pre-treatment process, high bonding strength between resistance welding oil and the copper surface is achieved.

Description

technical field [0001] The invention relates to the field of PCBs, in particular to a solder resist pretreatment process. Background technique [0002] A printed circuit board (Printed Circuit Board, PCB) is a mechanical support for the fixed assembly of various electronic components such as integrated circuits, and realizes wiring and electrical connections or electrical insulation between various electronic components such as integrated circuits. 1. A product that provides the required electrical characteristics (such as characteristic impedance, etc.). Printed circuit boards are generally composed of pads, vias, soldering layers, silk screen layers, copper wires, and various components. Usually, in order to increase the thickness of the copper skin, the green oil is removed by scribing on the solder mask layer, and then Adding tin achieves the effect of increasing the thickness of the copper wire. Solder mask production is an important process in the PCB manufacturing p...

AI Technical Summary

Problems solved by technology

The traditional pre-treatment method of solder mask is to use a combination of mechanical brushing and chemical micro-etching to process the board surface, but this method does not roughen the copper surface and holes of the PCB enough. Once the thick copper foil circuit board is made At this time, the bonding force between the ink and the copper layer is relatively weak, causing the solder resist oil to easily foam and fall off, which affects the subsequent PCB assembly