Excessive micro etching can cause substrate leakage at the pore opening, resulting in foaming around the pore opening; Insufficient micro etching can also cause insufficient bonding force, leading to foaming phenomenon; Therefore, it is necessary to strengthen the control of micro erosion; The micro etching depth for general copper deposition pre-treatment is 1.5-2 microns, and the micro etching depth for pattern electroplating pre-treatment is 0.3-1 microns. If conditions permit, it is best to control the micro etching thickness or rate through chemical analysis and simple experimental weighing methods; In general, the color of the slightly corroded board surface is bright, uniform pink, and without reflection; If the color is uneven or there is reflection, it indicates that there is a quality hazard in the pre-treatment of the process; Pay attention to strengthening inspections; In addition, the copper content of the micro etching tank, the temperature of the tank liquid, the load capacity, and the content of the micro etching agent are all items that need to be paid attention to;

　　Some reworked boards that have undergone copper deposition or graphic transformation may experience surface blistering during the rework process due to poor plating, incorrect rework methods, or improper control of micro etching time during the rework process, or other reasons; If poor copper deposition is found online during the rework of copper plate sinking, it can be directly removed from the line through water washing, acid washing, and rework without corrosion; It is best not to re degrease or slightly corrode; For boards that have already been thickened by electroplating, the plating should be removed from the micro etching groove now, and attention should be paid to time control. One or two boards can be used to roughly calculate the plating time to ensure the plating effect; After the stripping process is completed, a set of soft grinding brushes should be used on the brush plate machine to lightly brush, and then copper should be deposited according to the normal production process, but the etching time should be reduced by half or necessary adjustments should be made;