Analysis on the causes of excessive consumption of chloride ions in copper electroplating
at present, with the development of printed circuit boards to high density and high precision, more stringent requirements are put forward for sulfate copper plating process. It is necessary to control various factors that cause damage during the copper plating process due to transportation reasons in order to obtain high-quality coatings. In view of the excessive consumption of chloride ions in the copper plating process, the reasons for the excessive consumption of chloride ions are analyzed below
the antecedent of excessive chlorine ion consumption
when copper plating, the low current area of the circuit board surface appears "Matt", and the chlorine cube concentration is low, bell added; Generally, after adding hydrochloric acid, the "Matt" phenomenon of the coating in the low current density area of the plate surface can disappear, the chloride ion concentration in the plating solution can reach the normal range, and the plate surface coating is bright. If we want to solve the "Matt" phenomenon of the coating in the low current density area by adding a large amount of hydrochloric acid, it is not necessarily caused by the low concentration of chloride ion, and the real reason needs to be analyzed. If we add a large amount of hydrochloric acid: first, it may have other consequences; second, it will increase production costs, which is not conducive to enterprise competition
correctly analyze the cause of "matt coating in low current density area"
eliminate the phenomenon of "matt coating in low current density area" by adding a large amount of hydrochloric acid, indicating that if there is too little chloride ion, it is necessary to add hydrochloric acid to increase the concentration of chloride ion to reach the normal range, so that the coating in low current density area is bright. If it is necessary to add multiple times of hydrochloric acid to make the concentration of chloride ions reach the normal range? What is consuming a lot of chloride ions? However, at present, chloride ion is limited by the environmental concentration of all building materials markets. Too high concentration will make the brightener consume quickly. It shows that chloride ion will react with brightener, and excessive chloride ion will be consumed; Conversely, excessive brighteners also consume chloride ions. Because too little chloride ion and too much brightener are the main reasons for low electricity, its main technical parameters comply with gb1499.2 (2) 018 steel tubes for reinforced concrete Part 2: hot rolled ribbed steel bars and yb/t5126 (2) 003 "plan for plane reverse bending experiment of steel bars" and iso10065:1900 regulations and requirements on cold bending experiment and plane reverse bending experiment. Therefore, it can be seen that the coating in the flow density area is not bright "the main reason." The main reason for excessive consumption of chloride ion in copper plating is that the concentration of brightener is too high