Analysis and summary of the causes of poor electroplating on PCB boards?

Electroplating is a critical step in the PCB manufacturing process, and its quality directly impacts the performance and reliability of the final product. The following is an analysis of cases of poor electroplating on PCBs:

I. Analysis of Poor Electroplating Cases

1. Insufficient Hole Wall Copper Thickness: This often occurs during the electroplating process due to insufficient current density or insufficient plating time, resulting in insufficient copper thickness on the hole wall, which in turn affects electrical connection performance.

2. Insufficient Throwing Power: When the electroplated layer fails to penetrate to the expected depth, it may be due to improper concentration or temperature control of the plating solution, or poor performance of the electroplating equipment.

3. Overplating: Overplating occurs when the copper layer is excessively deposited in certain areas during the electroplating process, resulting in an uneven coating. This can be caused by uneven current distribution or excessive impurities in the plating solution.

4. Plating Debris: During the electroplating process, if the plating solution is contaminated, impurities may form on the surface of the plated layer, affecting its electrical performance.

5. Burned Plating: This often occurs when the plating temperature is too high or the current density is too high, causing the surface of the plating to become scorched, affecting both aesthetics and performance.

6. Rough Plating: If the plating solution is not clean enough or is not stirred sufficiently, the plating surface may become rough, affecting subsequent soldering performance.

7. Fracture at Hole Corners After Thermal Shock: In high-temperature environments, if the plating layer is not fully cured, it may fracture after thermal shock.

8. Loose Plating: If the plating layer has poor adhesion to the substrate, it may peel off during use, affecting circuit stability.

9. Poor Plating Ductility: If the plating layer has poor ductility, it may crack or break when bent or subjected to stress.

10. Incomplete Hole Fill: If the plating layer does not completely fill the hole, it may result in poor electrical connection.

11. Blowholes: In some cases, bubbles may form during the plating process, resulting in a hole without copper or a poor electrical connection.

12. No copper in the hole (dry film residue): If the dry film is not completely removed during the electroplating process, copper may be absent from the hole, affecting electrical connection performance.

13. No copper in blind vias: The absence of copper in blind vias can lead to poor electrical connections, requiring special attention to the plating quality of blind vias.

14. Wedge-shaped voids and plating cracks: These defects are often related to aging or contamination of the plating solution or improper equipment maintenance.