BGA chip refers to the abbreviation of Ball Grid Array packaging technology, which is a high-density surface mounting packaging technology. In the welding of BGA package chips, two different methods can be used: controlled temperature welding and hot pressure welding.
In controlled temperature soldering, vacuum thrust and alignment guide plates are used to accurately ensure the distance between the BGA chip and the PCB, and then the solder joints are exposed to the inlet wave peak and airflow is used to scrape away excess solder paste.
In hot pressure welding, the solder joint is first heated to an appropriate temperature to make it soft and plastic. Then, after the position is determined, a robot is used to press the BGA chip onto the PCB to complete the corresponding welding work.
The process of BGA chip welding is relatively complex and requires the use of special equipment and processes. Generally speaking, BGA soldering includes the following steps:
1. Prepare the chip and PCB: Place the chip on the PCB according to the BGA packaging method.
2. Fix the chip: Use solder paste to fix the chip on the PCB to prevent movement during the soldering process.
3. Heating the solder joints: Put the PCB into the heating furnace and heat it to the appropriate temperature to melt the solder paste.
4. Press the chip: After the solder paste melts, use a robot to press the chip onto the PCB so that the solder balls are aligned with the pads on the PCB.
5. Cooling and solidification: Let the PCB cool at a certain temperature to solidify the solder balls and pads.
6. Check the welding quality: Use X-ray and other testing equipment to check the welding quality to ensure that each solder joint meets the requirements.
The key to BGA soldering is controlling temperature and pressure, and ensuring alignment of solder balls and pads. If problems occur during the welding process, inspection equipment such as X-rays may be required for fault diagnosis and repair.