Judgment Method and Treatment of Bad Welding in BGA

Date：2023-10-17 14:42:50Views：211

BGA welding is a critical process in PCBA processing. However, due to the relative difficulty of inspection and maintenance after BGA welding, X-ray fluoroscopy must be used to ensure the reliability of the welding connection. Therefore, in PCBA processing, it is crucial to diagnose the defects in BGA welding, especially during reflow welding. This article will introduce the judgment method and handling of BGA welding defects.

Method for determining BGA welding defects:

1. X-ray testing: X-ray testing is a commonly used method for determining defects in BGA welding. By placing the BGA chip under an X-ray machine, the connection of solder joints can be observed, including their shape, position, size, etc., to determine whether the solder joints are well connected.

2. Thermal paper detection: Thermal paper detection is a simple method for determining BGA welding defects. Place the thermosensitive paper on the BGA chip for heating welding, observe the distribution of hot spots on the thermosensitive paper, and determine whether the solder joints are well connected.

3. Solder ball shape detection: Solder ball shape detection is a method of determining the connection status of solder joints by observing the shape of the solder ball. Observing the shape, size, and distribution of solder balls through a microscope can determine whether the solder joints are well connected.

4. Electrical testing: Electrical testing is a method of determining the connection of solder joints by testing parameters such as resistance and capacitance. By testing parameters such as resistance and capacitance, it is possible to determine whether the solder joint is well connected.

It should be noted that different judgment methods have their own advantages and disadvantages, and appropriate methods should be selected based on the specific situation for judgment. At the same time, when determining BGA welding defects, attention should be paid to the accuracy and reliability of the judgment results.

Treatment method for BGA welding defects:

1. Re hot air blowing welding: For the case of poor BGA welding, a hot air gun can be used to reheat the solder joint, allowing it to melt again and reconnect. This method is suitable for situations where the solder joints are not burned or damaged.

2. Solder joint repair: If the BGA solder joint has been burned or damaged, the solder joint repair method can be used for repair. This method requires the use of special welding tools and materials to rebuild the solder joints.

3. Replace BGA chip: If there are problems with the BGA chip itself or if the solder joints are severely damaged and cannot be repaired, it is necessary to replace the BGA chip. This method requires a re BGA welding process to ensure the reliability of the solder joint connection.

4. Inspection and adjustment of welding process: The reason for poor BGA welding may be incorrect welding process, which requires inspection and adjustment. For example, adjusting parameters such as welding temperature, time, and atmosphere to ensure the reliability of solder joint connections.

It should be noted that the treatment method for BGA welding defects should be selected based on the specific situation to ensure the reliability of welding joint connections and product quality. At the same time, efforts should be made to prevent the occurrence of BGA welding defects during the production process, such as optimizing the welding process, using high-quality materials and equipment, etc.

In summary, the judgment and treatment methods for BGA welding defects vary, and appropriate methods should be selected based on the specific situation for treatment. At the same time, when conducting BGA welding, attention should be paid to controlling parameters such as welding temperature, welding time, and welding pressure to ensure welding quality.