In order to prevent problems such as bridging of solder balls in the electronic connection process of BGA or FlipChip packaging with finer pitches, and to use the "self-alignment effect" of solder balls in the melting process, the solder balls used in BGA packaging, It has very high dimensional and shape precision requirements. In order to produce solder balls that meet the requirements of solder ball surface quality and dimensional accuracy, various technologies have been tried and some technical solutions have been used in production, but in order to obtain better production technologies, there are still quite a few domestic and foreign Research is invested in solder ball production technology.

There are generally two manufacturing processes for solder balls, namely the quantitative cutting method and the vacuum spraying method. The former is more suitable for larger diameter solder balls, the latter is more suitable for small diameter solder balls, and can also be used for larger diameter solder balls. The physical and electrical performance requirements of solder balls mainly include density, solidification point, thermal expansion coefficient, volume change rate during solidification, specific heat, thermal conductivity, electrical conductivity, resistivity, surface tension, tensile strength, anti-fatigue life and extension rate etc. In addition, the diameter tolerance, roundness, and oxygen content of solder balls are also regarded as key indicators for the current quality level competition of solder balls.

Future technology development trend of tin ball

Vigorously developing solder ball technology is one of the important contents in the development of new semiconductor packaging. Especially the current development of my country's lead-free solder ball is a top priority.

With the development of BGA packaging technology, based on the consideration of production cost, efficiency, product quality and other factors, the traditional solder ball manufacturing technology will eventually be replaced by the uniform droplet method. Because the uniform droplet method is a novel technology, it has many advantages for producing BGA packaging solder balls, so more energy is invested in its application and research at home and abroad.