How to print soldering flux on the bottom pad of BGA
In general, Use flux soldering of high viscosity, to splice and process, should ensure that the printing pattern is clear, the overflow flux.
When printing, BGA special small template is used. The thickness and opening size of the template should be determined according to the ball diameter and the ball distance.
After printing, the printing quality must be checked. If it is unqualified, it must be printed again after cleaning.