The materials involved in the enclosure / electronic device play a vital role for the understanding on device reliability. During long term exposure to varying atmospheric conditions, the parameters such as water adsorbtion and diffusion of ex. cabinet materials are of great importance.
Quantification of water uptake by unit area of a typical PCBA surface with and without components under humidity and temperature conditions: Weight gain measurements
• Testing the effect of cleanliness of PCBAs on water uptake (Flux residue - effect of various soldering processes such as reflow, wave, and selective): Weight gain measurements
• Investigation on the effect of water layer formation on electrical functionality: DC leakage current (LC) and AC impedance studies using surface insulation resistance pattern (SIR)
• Investigation of typical hygroscopic contamination in reducing critical humidity levels for condensation, and effect on LC and impedance
• Testing typical contamination and humidity levels causing failure such as electrochemical migration (ECM): DC leakage current measurement, impedance, and post-failure analysis using FEG-SEM and IR microscopy.
Video below shows examples on how different laminates, residues and components influence the water layer formation