Why is PCBA cleaning very important?
The most intuitive effect of PCBA contaminants is the appearance of PCBA. If placed or used in a high temperature and high humidity environment, the moisture absorption and whitishness of the residue may occur.
Due to the large use of leadless chips, micro BGAs, chip scale packages (CSP) and 01005 in components, the distance between components and boards is reduced, the size is miniaturized, and the assembly density is also increasing. If the halide is hidden under the component, local cleaning may cause catastrophic consequences due to halide release. Remote Control PCB solution
2, three anti-paint coating needs
Prior to surface coating, resin residues that are not washed away can cause delamination or cracking of the protective layer; active agent residues can cause electrochemical migration under the coating, resulting in failure of coating crack protection. Studies have shown that 50% coating adhesion can be increased by cleaning. Halogen free pcb factory china
3, no cleaning also needs cleaning
According to current standards, the term no-clean means that the residue of the board is safe from a chemical point of view and does not have any effect on the board's production line and can be left on the board. Detection of corrosion, SIR, electromigration, and other specialized detection methods are primarily used to determine the halogen/halide content to determine the safety of the no-clean assembly after assembly.
However, even with the use of a low solids no-clean flux, there will be more or less residue, and for products with high reliability requirements, no residue or contaminants are allowed on the board. For military applications, even disposable electronic assemblies require cleaning.