In recent years, the issue of ionic contamination in electronic boards has gained increasing importance. With the latest revision of the J-STD 001 standard, the technical committees of the Association Connecting Electronics Industries (IPC) have introduced a new perspective on evaluating the quality of devices produced using such components.
Some of the anomalies found in electronic boards can be traced back to contamination due to production residues. The contamination value represents the set of residual pollutants from manufacturing processes that remain on an electronic system. These residues can be ionic or non-ionic: ionic residues consist of atoms or molecules/particles that can dissolve as ions in a water/alcohol solution, potentially becoming conductive (dendritic formations) under certain environmental or usage conditions of the boards, which may lead to functional defects and reliability issues over time.
Non-ionic residues consist of elements without any conductive properties, and while they may remain on the board after production and assembly, they do not cause functional problems.
For this reason, in terms of electronic device reliability, attention has shifted towards the ionic residue content in PCBA and the integrated PCB, rather than other residues.
Ionic compounds that may be present during PCB and PCBA production include:
• Salts
• Organic and inorganic acids
• Flux activators
• Chemical agents from metal plating processes (only for PCBs)
• Human sweat
The overall residual ionic content on a printed circuit or electronic board is the result of these compounds, each of which can induce specific, varying degrees of adverse effects, depending on its quantity.
Therefore, Nortech Elettronica is committed to supporting customers in the analysis and prevention of issues related to ionic contamination. The company has equipped itself with an analytical instrument to conduct tests and monitor the process and product, following an agreement with the customer.
