Peridynamic Solution of Wetness Equation with Time Dependent Saturated Concentration in ANSYS Framework

The components of Integrated Circuit (IC) devices are susceptible to moisture absorption at different stages of the production environment which can lead to hygrothermal stresses during the surface mounting process. The moisture concentration in electronic packages can be determined based on the wetness approach. If the saturated concentration value is dependent on temperature or time, the analogy between the wetness equation and the standard diffusion equation is not valid and requires special treatment. In this study, an alternative formulation, peridynamics, is utilized for the solution of wetness field equation in the case of saturated concentration varying with time. The formulation is implemented in the commercial finite element software, ANSYS, by utilizing traditional finite elements and solvers to make the computations more efficient. The peridynamic wetness approach is validated by considering various problem cases for absorption and desorption with multi-material systems representative of electronic packages.