pcb circuit board processing process may cause the board surface quality is bad in which 4 kinds of situations?
1, the problem of substrate technology processing: especially for some thinner substrates (generally below 0.8mm), because the substrate is less rigid, it is not appropriate to use the brush board machine to brush the board. This may not be able to effectively remove the substrate production and processing process to prevent the board surface copper foil oxidation and special treatment of the protective layer, although the layer is thin, brush board is easier to remove, but the use of chemical treatment there are greater difficulties, so in the production and processing of important attention to control, so as not to cause the board surface substrate copper foil and chemical copper between the poor bonding caused by the board surface blistering problem; this problem in the thin inner layer for blackening, when There will also be blackening browning bad, uneven color, local black browning not on the problem.
2, the board surface in the machining (drilling, lamination, milling, etc.) process caused by oil or other liquid staining dust pollution surface treatment of the phenomenon of poor
3, sink copper brush plate bad: sink copper before grinding plate pressure is too large, resulting in hole deformation brush out of the hole copper foil rounded or even hole leakage base material, so that in the process of sink copper plating tin spray welding, etc. will cause hole blistering phenomenon; even if the brush plate does not cause leakage base material, but too heavy brush plate will increase the roughness of the hole copper, and thus in the micro-etching roughing process of the copper foil is very easy to produce roughing over phenomenon, there will be a certain quality of hidden trouble; therefore, we should pay attention to strengthen the control of the brush plate process, can be through the abrasive mark test and water film test will brush plate process parameters to adjust to.
4、Water washing problem: Because the sink copper plating treatment to go through a large number of chemical potion treatment, all kinds of acid and alkali and organic and other drugs and solvents, the board surface water washing is not clean, especially the sink copper adjustment degreasing agent, will not only cause cross-contamination, but also cause the board surface local treatment or poor treatment effect, uneven defects, resulting in some bonding problems; Therefore, we should pay attention to strengthen the control of water washing, mainly including the flow of cleaning water, water quality, washing time, and the board drip