Solder joints properties assessment in the terms of 4P Soldering Model

The challenges for the companies involved in conception, development and/or manufacturing of electronic products are the lead-free technology with its increased melting temperature of the solder alloy and trend to reduce the solder materials cost by usage of lead-free solder pastes with low silver content. Defining the elements Pad-Paste-Pin-Process as Key Process Input Variables (KPIV) in terms of 4P Soldering Model concept [1, 3], the solder joints are result of KPIV synergistically interactions and correlations, with consequences over their microstructure. In the paper, taking into consideration the cooling rate influence over intermetallic compounds formation and microstructure, are presented the investigations over electrical, and mechanical properties of solder joints resulted from Vapour Phase Soldering (VPS) process in terms of 4P Soldering Model. Maintaining PAD and PIN of KPIV as references were study the solder joints properties determined by PASTEs as function of cooling rate parameters of VPS PROCESS. The results of the studies performed and presented in the paper will be used for improving process control in order to minimize losses on VPS lines, to reduce defects numbers and rework time in order to achieve “zero defects production”.