Postreflow

Postreflow is a process used in the manufacturing of printed circuit boards (PCBs) to ensure the solder joints are properly formed and the board is free of defects. It is typically performed after the initial reflow process, which involves heating the PCB to melt the solder and form the joints. The purpose of postreflow is to inspect the board for any issues that may have occurred during the initial reflow process, such as solder bridges, missing solder, or poor solder wetting.

During postreflow, the PCB is visually inspected using automated optical inspection (AOI) systems or manual inspection. The AOI systems use high-resolution cameras to capture images of the PCB and analyze them for defects. The manual inspection involves a trained inspector who visually examines the PCB for any visible defects.

If any defects are found during postreflow, corrective actions may be taken. For example, if a solder bridge is detected, it may be removed using a soldering iron or a desoldering tool. If missing solder is detected, it may be added using a soldering iron or a hot air rework station. If poor solder wetting is detected, it may be corrected by reflowing the solder joint.

Postreflow is an important step in the PCB manufacturing process, as it ensures that the solder joints are properly formed and the board is free of defects. By performing postreflow, manufacturers can improve the reliability and performance of their PCBs.