Effective modeling of the reflow soldering process: basis, construction, and operation of a process model

Thermal history variation within printed circuit assemblies (PCAs) during reflow soldering is considered one of the main drivers for manufacturing defects. It is recognized that predictive tools could be used to identify the temperature variations that arise during the reflow process and, in conjunction with experimentally derived data, determine their impact on manufacturing quality. This paper describes the development of representative process models of the reflow soldering of PCAs and outlines some of the more important parameters to consider for accurate simulation of the reflow process. This first part also presents results which illustrate the variation with temperature of critical properties for electronic materials, such as for common substrate and epoxy based packaging materials.