Category Archives: SMT


Apr03
PCB Warping and Bowing: Causes, Prevention, and Best Design PracticesPCB warpage

A user asked: “During the SMT process, PCBs often warp or bow after going through reflow high temperature. In severe cases, this can lead to defects like insufficient solder joints or tombstoning. How can we prevent and solve this issue?” … Continue reading

Mar27
Does PCB Solder Mask Misalignment Lead to BGA Soldering Defects?

Recently, our company started a new project, and the R&D team has been pushing PCB layout requirements to the extreme. As PCBs size get smaller, the solder mask (S/M) design must also shrink accordingly. However, our current PCB manufacturers struggle … Continue reading

Feb27
What Is Solder Mask (S/M)? What Is Its Purpose on a PCB? Why Is It Usually Green?

In discussions about printed circuit boards (PCBs), you’ll often hear the term Solder Mask (S/M). But what exactly is a solder mask, and what role does it play in a PCB? Some also refer to it as solder resist. What … Continue reading

Feb20
PCB Popcorn Effect: Why it Happens and How to Stop It

The main reasons for PCB delamination or “popcorning” are primarily (1) moisture absorption and (2) excessive α2/Z-axis CTE (Coefficient of Thermal Expansion). Among these, moisture absorption is responsible for about 70% of delamination issues. Other factors, such as uneven thermal … Continue reading

Feb06
Causes of Solder Empty and Tombstoning in Small Chip of Resistors and Capacitors

Recently, some people have asked about issues with solder empty in small chip SMD components like resistors and capacitors. Even after thoroughly checking the reflow oven profile settings and confirming everything is correct, solder empty still frequently occur with these … Continue reading