Introduction To The Importance Of PCBA Cleaning Process

“Cleaning” is often ignored in the PCBA manufacturing process of the printed circuit board and is not considered a key step. However, with the long-term use of the product in the client, the problems caused by ineffective cleaning in the early stage lead to many faults, and the operation cost of repairing or recalling products increases sharply. The following is a brief description of the PCB (circuit board) PCBA cleaning role.

 

During the production of PCBA (printed circuit components), there are many technological stages, and each stage is contaminated to different degrees. Therefore, various deposits or impurities remain on the PCBA surface of the circuit board (circuit board), which may reduce product performance or even cause product failure. For example, solder paste and flux are used for auxiliary welding in the process of welding electronic components, and residues are generated after welding, which contains organic acids and ions, etc., among which organic acids will corrode the circuit board (circuit board) PCBA, and the presence of electric ions may lead to short circuit, resulting in product failure.

 

There are many kinds of pollutants on the PCB (circuit board) PCBA, which can be classified into the ionic type and non-ionic type. Ionic pollutants come into contact with moisture in the environment, and electrochemical migration occurs after electrification, forming dendritic structures, resulting in low resistance pathways and damaging PCBA functions of circuit boards (circuit boards). Nonionic pollutants can penetrate the insulation layer of PCB and grow dendrites under the surface layer of PCB. In addition to ionic and non-ionic pollutants, there are granular pollutants, such as solder ball, floating-point in the solder tank, dust, dust, and so on, these pollutants will lead to solder joint quality reduction, welding point, produce pores, short circuit, and a variety of adverse phenomena.

 

Of all the pollutants, which are getting the most attention?

Flux and solder paste is generally used in the reflow soldering and wave soldering process, which is mainly composed of solvent, wetting agent, resin, a variety of ingredients such as corrosion inhibitor and activator, there must be after welding thermal modification products, all these substances in the dominant pollutants, from product failure situation, residues after welding are the most important influence factors of affecting product quality, ionic residue decreased insulation resistance, easy cause electric migration rosin resin residue easy adsorption of dust or impurity causing increased contact resistance, serious cause the open circuit failure, therefore must carry out strict cleaning after welding, to the quality of the protection circuit board (PCB) PCBA.

 

To sum up, it is very important to clean the PCBA of the board. “Cleaning” is an important process directly related to the quality of the PCBA of the printed circuit board, which is indispensable.