Today, with the rapid development of science and technology, various high-tech electronic products emerge in endlessly, which makes circuit board manufacturers more and more strict on the quality of plates. So, what quality problems are most likely to occur in the PCB production process of PCB factory?
1. The dimension of substrate changes due to the difference of latitude and longitude directions.
Solution: Determine the warp and weft directions, and compensate on the negative according to the shrinkage rate; At the same time, when cutting, it is processed in the fiber direction, or according to the character mark provided by the manufacturer on the substrate.
2. Part of the copper foil on the surface of the substrate is etched away, resulting in dimensional change when the stress is relieved.
Solution: When designing the circuit, we should try our best to make the whole board circuit evenly distributed; At least a transition section must be left in the space (mainly without affecting the circuit position).
3. When the PCB factory brushes the board, the pressure is too high, resulting in compressive and tensile stress and deformation of the substrate.
Solution: Try brushing should be adopted to make the process parameters in the best state, and then rigid plate should be made.
4. The resin in the substrate is not completely cured, resulting in dimensional change.
Solution: Bake the solution. Especially before drilling, baking at 120℃ for 4 hours continuously to ensure the curing of the resin.
5. Before lamination, the storage condition of multilayer board is poor, which makes the thin substrate or prepreg absorb moisture, resulting in poor dimensional stability.
Solution: The inner layer of the substrate is oxidized, baked to remove moisture, and the treated substrate is stored in a vacuum drying oven.
6. When the multilayer board is pressed, excessive glue flow causes the deformation of the glass cloth.
Solution: It is necessary to carry out process pressure test, adjust process parameters and then press. At the same time, according to the characteristics of prepreg, an appropriate amount of glue can be selected.