BGA is a type of chip packaging, abbreviation of English (Ball Grid Array), the packaging pins are spherical grid array at the bottom of the package, and the pins are spherical and arranged into a pattern similar to a grid, so it is named BGA. The following is a collection of questions about BGA welding in SMT chip processing, let's find out together.
1. BGA package.
1. What is BGA packaging?
BGA packaging is a high-density, high-reliability and high-heat dissipation packaging technology for electronic components. It connects chips and printed circuit boards through spherical solder joints, and is widely used in modern electronic products, especially suitable for chips with high integration and high power consumption, such as high-performance integrated circuits such as microprocessors and graphics chips.
2. BGA package features.
a. High-density cabling capability;
b. Reduce signal interference;
c. Improve heat dissipation performance;
d. Easy to automate manufacturing;
e. Provide mechanical stability;
2. BGA welding process.
1. Solder paste printing. The appropriate amount of solder paste is printed onto the pads of the PCB board by the machine to ensure that the pads corresponding to the SMD components and the PCB can achieve good electrical effects and complete the soldering purpose during reflow soldering
2. Component placement. Place the SMD components accurately on the position of the printed solder paste, and place the components according to the requirements of the PCBA product
3. Reflow soldering. As a key process in SMT production, reasonable temperature curve setting is the key to ensure the quality of reflow soldering, and improper temperature curve will cause PCB board soldering defects such as incomplete soldering, virtual soldering, component warping, and excessive solder balls, which will affect product quality.
4. AOI X-ray inspection. It can check all the process defects, check the shape of the solder joints through its perspective characteristics, and compare the shape with the standard in the computer library to judge the quality of the solder joints, especially for the solder joint inspection of BGA and DCA components, which is irreplaceable.
3. Analysis of the causes of BGA welding defects.
1. BGA pad holes are not treated. BGA soldering has holes on the pads, and the solder balls are lost along with the solder during the soldering process, and due to the lack of resistance soldering process in PCB production, the solder and solder balls are lost through the holes close to the solder plate, resulting in the loss of solder balls.
2. The size of the pad is different. BGA welding pads are of different sizes, which will affect the quality and yield of welding, BGA pad outlet, more information about EMS intelligent manufacturing (PCBA foundry material, SMT chip processing) and other information, you can enter Anhui Interli**www.wwwaitpbca.com view.