1、 Copper or tin plated lead with infiltration plating

Solution to the cause

1. Poor dry film performance, exceeding the expiration date for use. Try to use dry film within the effective range.

2. Poor cleaning or rough surface of the substrate, and weak adhesion of the dry film. Strengthen the surface treatment of the board.

4. Over exposure, the corrosion inhibitor becomes brittle. Use an optical density ruler to correct the exposure amount or exposure time.

5. Under exposure or over development can cause the resist to become hairy and curly. Correct exposure, adjust development temperature and speed.

6. The temperature of the pre-treatment solution before electroplating is too high. Control the temperature of various pre-treatment solutions before plating.

2、 Bubbles appear between the dry film and the surface of the copper foil

Solution to the cause

1. When the film temperature is too high, the volatile components in the corrosion inhibitor rapidly evaporate, remaining between the polyester film and the copper clad foil, forming bubbles. Adjust the film temperature to within the standard range.

2. The surface of the hot pressing roller is uneven, with pits or scratches. Pay attention to protecting the flatness of the surface of the hot press roller, and do not use hard or sharp tools to scrape when cleaning the hot press roller.

3. The pressure of the pressure roller is too low. Increase the pressure between the two pressure rollers appropriately.

4. The board surface is uneven, with scratches or dents. Select the board and pay attention to the previous process to reduce the possibility of scratches and dents.

3、 After development, the dry film image becomes blurry, and the resist becomes dark and hairy

Solution to the cause

1. Insufficient exposure. Calibrate the amount of light or exposure time in the path using an optical density ruler

2. The minimum light density of the photographic plate is too high, which hinders ultraviolet light. Check the photographic plate before exposure.

5. The temperature of the developer is too high or the development time is too long. Adjusting the transfer speed during the detachment and development of the developer solution