PCB & PCBA Manufacturer
The delicate process of reflow soldering must prevent micro-defects common in small components.
1. Precise Reflow Profiling: The reflow profile (heating, soaking, peak, and cooling zones) must be meticulously optimized. A profile that is too steep can cause component tombstoning (where surface tension pulls one end of the component up), while insufficient heat leads to cold joints.
2. Nitrogen Atmosphere: Using a Nitrogen (N2) atmosphere in the reflow oven is often required for high-reliability, micro-pitch assemblies. Nitrogen prevents oxidation, improving solder joint wetting and ensuring maximum joint strength and quality.
3. Advanced Inspection (AOI and X-Ray): After reflow, High-Resolution AOI is essential for detecting misalignment. Automatic X-Ray Inspection (AXI) is mandatory for checking solder joint quality and voids under non-visible packages like BGA and QFN, which often accompany fine-pitch components on high-density boards.