9.3 Stencil
The recommended stencil thickness is at least 0.15 mm to 0.20 mm.
9.4 Solder Paste
The thickness of the solder paste and the flatness of the PCB are essential for the production yield.
It is recommended to use the same kind of leaded solder paste used during the production process of
Neoway.
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The melting point of the leaded solder paste is 35℃ lower than that of the lead-free solder
paste, and the temperature in the reflow process parameters is also lower than that of the lead-
free solder paste. Therefore, the soldering time is shorter accordingly, which easily causes a
false solder because LCC/LGA in the module is in a semi-melted state during the secondary
reflow.
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When using only solder pastes with lead, please ensure that the reflow temperature is kept at
220°C for more than 45 seconds and the peak temperature reaches 240°C.
9.5 SMT Oven Temperature Profile
Thin or long PCB might bend during SMT. So, use loading tools during the SMT and reflow soldering
process to avoid poor solder joint caused by PCB bending.
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