Multi-Layer Thick Copper PCB Board Foaming Prevention Measures

Multi-layer thick copper PCB board foaming prevention measures

One. Cause analysis:

1. Poor plate quality

PCB board quality does not meet the requirements, such as insufficient adhesion of copper foil, unstable performance of insulating layer material, etc., will lead to the stripping of copper and substrate, forming bubbles.

2. Environmental factors

High air humidity or poor ventilation will cause the copper sheet to blister. If the PCB board is stored in a humid environment or during the manufacturing process, the moisture will penetrate between the copper and the substrate, making the copper bubble.

3. Processing temperature

During the production process, the processing temperature is too high or too low, which will make the PCB surface in a non-insulated state, resulting in oxides when the current flows through, forming bubbles.

4. Foreign objects on the surface

There is oil, water, etc., on the copper skin, which will make the PCB surface in a non-insulating state, resulting in oxides when the current flows through, forming bubbles.

5. Process factors

In the production process, the roughness of the orifice copper may be increased, foreign bodies may be contaminated, and the orifice may leak the substrate.

6. Current factor

In the plating process, the uneven current density will cause the plating speed in some areas to be too fast, resulting in bubbles.

Two. Preventive measures

1. Optimize circuit design

In the design stage, the current distribution, line width, line spacing, aperture and other factors should be fully considered to avoid local overheating caused by improper design. In addition, appropriately increasing the wire width and spacing can reduce the current density and reduce heating.

2. Choose high-quality plates

When purchasing PCB board, you should choose a reliable quality supplier to ensure that the quality of the board meets the requirements.

3. Strengthen production management

Develop strict process flow and operation specifications to ensure quality control in all aspects of the production process. In the plating process, control the temperature during the plating process, ensure uniform current density, use high-purity electrolyte, and perform good substrate surface treatment to ensure surface cleaning and activation.

Three. Solution measures

1. Remove the vacuum

For the PCB board that has blistered, it can be repaired by re-vacuuming. During the repair process, attention should be paid to controlling the temperature and pressure to avoid further damage to the PCB.

2. Bake over heat

Heating and baking is one of the common ways to solve the blistering of PCB copper sheet. This method is simple and effective. However, it is necessary to strictly control the temperature and time during the baking process to avoid excessive heating or burning of the PCB board.

In short, strengthening production management and standardized operation is the key to avoid the blistering of PCB copper sheet. It is hoped that the content of this article can provide useful reference and help to the majority of electronic industry practitioners in solving the problem of PCB copper sheet foaming.