Category Archives: SMT


Jul22
What purpose of alloy metal of Cu, Ag, Zn, Sb, Bi added to solder paste?

Tin (Sn) based solder is still the best material for PCB (Printed Circuit Board) assembly in the modern industry today. The only difference is the lead (Pb) free from the solder base due to environmental concerns. The melting point of … Continue reading

Nov13
Why BGA soldering ball always crack(3)? IMC layer growth is a certain result to form the soldering joints

The Intermetallic Compound (IMC) layer grows in the interface between Cu-based, Ni-based and Sn-solder is the certain result of the chemical reaction that forming the soldering joint. But the IMC layer is also the weakest location of the solder bonding-force. … Continue reading

Oct30
Why BGA soldering ball always crack(2)? The composition of PCBA bonding-force

This article will talk about the composition of the PCBA bonding-force. There are numerous factors and elements involved in PCBA bonding force. However, Workingbear believes that we can utilize the findings of the red dye test to examine this issue. … Continue reading

Sep25
Why BGA soldering ball always crack(1)? Stress > bonding-force

What is the actual root cause of  BGA solder ball cracking? Stress is higher than its bonding-forces. The root cause of BGA solder ball cracked is stress higher than bonding-forces. Stress is higher than bonding-force is the certain result of … Continue reading

Nov14
How to print solder paste on PC Board and screen printing notices?

Printing the solder paste on the PCB (Printed Circuit Board) and go through reflow oven to re-melt the solder paste and solder the electronic components on PCB is most common process in today’s electronics manufacturing industry. Printing the solder paste … Continue reading