BGA encapsulated memory: BGA encapsulated I/O terminals are distributed under the package in the form of circular or columnar solder joints. The advantage of BGA technology is that although the number of I/O pins increases, the pin spacing does not decrease, but increases, thus improving the assembly yield. Although its power consumption increases, BGA can be welded by controllable collapse chip method, thus improving its electrothermal performance. Compared with the previous packaging technology, the weight and parasitic parameters are reduced, the signal transmission delay is reduced, and the use frequency is greatly increased. The assembly can be welded in coplanar with high reliability.
TinyBGA encapsulated memory: The volume of memory products using TinyBGA encapsulated technology is only 1/3 of that of TSOP encapsulated under the same capacity. The lead of TSOP encapsulated memory is drawn around the chip, while TinyBGA is drawn from the central direction of the chip. This method effectively shortens the transmission distance of the signal, and the length of the signal transmission line is only 1/4 of the traditional TSOP technology, so the attenuation of the signal is also reduced. This not only greatly improves the anti-interference and anti-noise performance of the chip, but also improves the electrical performance.
Substrate or intermediate layer is a very important part of BGA packaging. It can be used not only for interconnection, but also for impedance control and inductance/resistance/capacitance integration. Therefore, the substrate material is required to have high glass transition temperature rS (about 175-230 C), high dimensional stability and low moisture absorption, and good electrical performance and high reliability. Metal film, insulating layer and substrate medium also have high adhesion performance.