In the PCBA packaging process, solder mask is a very important coating material. Provides a dielectric and mechanical shield to the PCBA board during and after soldering and prevents solder deposition in this location. Commonly used welding films in electronic processing plants are liquid film and dry film.

Solder mask ink is very important in PCBA processing and SMT, its main function is to protect the circuit board, prevent the conductor from getting wet, prevent short circuit caused by influence and moisture, prevent unqualified processing, open circuit due to contact, etc., yes The guarantee that the PCBA board can be used normally in harsh environments. The following is a brief introduction to the poor solder film design in PCBA packaging processing:

1. Pad via line. In principle, resistance soldering should be done on the wires between the vias that connect to the pads.

   
   

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2. The resistance welding design between the pads and the pads, the pattern specification of the resistance welding should conform to the welding end distribution design of the specific components: if the window resistance welding is used between the pads and the pads, the There should be no short circuit.

3. The size of the resistance welding diagram of the components is improper, and the design of the resistance welding diagram is too large, which will "shield" each other and lead to open welding, so that the distance between the components is too small.

4. There is no resistance welding film in the lower hole of the module, and there is no resistance welding hole under the module. After wave soldering, the solder on the hole may affect the reliability of IC soldering, and may also cause defects such as short circuit of components.

The above are the factors that cause the PCBA solder mask to be damaged. I hope the above little knowledge can help you!