Reactive Die Bonding on LTCC Substrates – Analysis by CFD Simulation

To improve the understanding of reactive multilayer systems as a joining process computational fluid dynamics (CFD) simulations have been performed and compared with experimental measurements made using a pyrometer. These CFD simulations consist of a shoebox model which contains different layers. The layers in the model are an Ni/Al reactive multilayer, low temperature co-fired ceramic (LTCC) substrate and the surrounding air environment. To simulate the heat released by the multilayer system, a user defined function of probability density function (PDF) form was written for the heat source. The peak energy intensity, reaction width and reaction speed can be controlled via the PDF to adapt the simulation to the real model.