Analysis of the influence and mechanism of the pollution condensation environment on the electrochemical migration behaviour of printed circuit board with immersion silver

A refrigeration device was developed to induce condensation on printed circuit board with immersion silver (PCB-ImAg). Results show that in a condensation environment with low relative humidity, an electrolyte film can still be formed that allows conduction between the two poles of PCB-ImAg, allowing the thermodynamic conditions for electrochemical migration (ECM) to be reached and creating the risk of short-circuit failure. Under high relative humidity, the main body of ions that underwent ECM on the surface of PCB-ImAg was Cu2+ and as the relative humidity of the environment increases, the short-circuit failure time shortens, and the initial current density increases.