Main factors affecting OSP film thickness

The effectiveness of oil removal directly affects the quality of film formation. Poor oil removal results in uneven film thickness. On the one hand, the concentration can be controlled within the process range by analyzing the solution. On the other hand, it is necessary to regularly check whether the oil removal effect is good. If the oil removal effect is not good, the oil removal fluid should be replaced in a timely manner.

The purpose of micro etching is to form a rough copper surface for easy film formation. The thickness of micro etching directly affects the rate of film formation. To form a stable film thickness, it is necessary to maintain the stability of micro etching thickness. It is generally appropriate to control the micro etching thickness between 1.0 and 1.5.

Pre immersion can prevent harmful ions such as chloride ions from damaging the OSP cylinder solution. The main function of OSP pre impregnation cylinder is to accelerate the formation of OSP film thickness and deal with the impact of other harmful ions on OSP cylinder. The presence of an appropriate amount of copper ions in the pre impregnation solution can promote the formation of complex protective films and shorten the impregnation time. It is generally believed that due to the presence of copper ions, alkylbenzimidazole has a certain degree of complexation with copper ions in the pre welding flux solution. When this complex with a certain degree of polymerization is deposited onto the surface of copper to form a complex film, it can form a thick protective layer in a short period of time, thus acting as a complexing promoter. If the content of alkyl benzimidazole or similar components in the prepreg is very small, when the copper ion is excessive, the prepreg solution will age prematurely and need to be replaced. Therefore, it is necessary to focus on controlling the concentration and duration of the pre leaching solution.

Concentration of the main components of OSP

Alkyl benzimidazole or similar components are the main components in OSP solution, and the concentration is the key to determine the thickness of OSP film. During the production process, it is necessary to focus on monitoring the concentration of OSP solution.

PH value of the solution

The stability of the PH value has a significant impact on the film formation rate. In order to maintain the stability of the PH value, a certain amount of buffer is added to the solution tank. A dense, uniform, and moderately thick OSP film can be obtained by controlling the PH value between 2.9 and 3.1. When the PH value is on the high side, when PH greater than 5, the solubility of alkyl benzimidazole decreases, and oil like substances are precipitated; When the PH value is low and less than2, the formed membrane will be partially dissolved.

Temperature of solution

The change in temperature also has a significant impact on the film formation rate. The higher the temperature, the faster the film formation rate. Therefore, it is necessary to control the temperature of the OSP tank.

Film formation time

Under the determined composition, temperature, and PH value of OSP tank solution, the longer the film formation time, the thicker the film formation. Therefore, it is necessary to control the film formation time.