Comprehensive Moisture Diffusion Characteristics of Epoxy Molding Compounds Over Solder Reflow Process Temperature

This is the authors' abstract. We don't add key points for this paper.

We address moisture diffusion in epoxy molding compounds (EMCs) at temperatures higher than 100°C. The objectives of this paper are thus: 1) to obtain diffusion properties of EMCs in both absorption and desorption modes at a wide range of temperatures; 2) to establish a non-Fickian correlation for diffusivity; and 3) to assess moisture diffusion behaviors during a solder reflow process, described by two different Fickian diffusivities of absorption and desorption and the non-Fickian diffusivity. An experimental procedure is established to measure the diffusivity and solubility of selected EMC materials. The results are utilized in a numerical simulation to analyze the effect of the non-Fickian diffusion characteristics on the moisture distribution during the reflow process.