BGA technology (Ball Grid Array Package) is the ball grid array package technology. The emergence of this technology has become the best choice for high-density, high-performance, multi-pin packages such as CPU, motherboard south and north bridge chips. However, the BGA package occupies a larger area of the substrate. Although the number of I/O pins of this technology increases, the distance between the pins is much larger than that of QFP, which improves the assembly yield. And this technology uses a controllable collapse chip method for welding, which can improve its electrothermal performance. In addition, the assembly of this technology can be coplanar welding, which can greatly improve the reliability of the package; and the packaged CPU realized by this technology has a small signal transmission delay, and the adaptation frequency can be greatly improved.