Looking at the Development of BGA Packaging From the Perspective of SMT Processing and Welding

From the perspective of SMT welding, the mounting tolerance of BGA chips is 0.3mm, which is much lower than the previous QFP chip mounting accuracy requirement of 0.08mm. Generally speaking, SMT patch proofing and placement are done in a space of the size of a little finger or even smaller, then a larger placement tolerance means higher reliability and placement accuracy.

Then we assume that a large-scale integrated circuit has 400 I/O electrode pins, the same pin spacing is 1.27mm, and the traditional QFP chip has 4 sides, each side has 100 pins, then the final side length is at least 127mm so that the entire chip surface area should be 160 (square centimeters).

If we use the BGA package to process, then the electrode pins of the final SMT chip are evenly arranged under the chip in 20*20 rows, and the side length only needs to be 25.4mm at most, and the volume is less than 7 (square centimeters).

From the above analysis, we can conclude 2 great improvements:

1. The number of chip soldering pins decreases
As the saying goes: “The more you do, the more mistakes you make.” The opposite is that we reduce the number and procedures of welding as little as possible, so the probability of error will become less. Therefore, the reduction of the number of soldered pins is an important method that can improve the quality and reliability of welding. It can be said indirectly that BGA packaging has huge technical advantages and development potential compared to traditional QFP packaging.

2. Welding volume becomes smaller
From the brain interface of Tesla CEO Elon Musk to the skin display, what we see is not only technological progress but also an application of highly intelligent and miniaturized products. There is a computer weighing a few kilograms in the sky, so the change in soldering volume also conforms to a future development trend, and it is also a huge late-comer advantage of BGA packaging.

Therefore, whether it is from PCBA labor package or the future development trend, our development of BGA packaging has a bright future.