ADDITIVATED SOLDER PASTE AND PROCESS FOR APPLYING A REACTIVE ADDITIVE ELEMENT FOR SELECTIVE CONTROL OF SOLDERING TEMPERATURE ON THE REFLOW SOLDERING METHOD

摘要

The present application concerns an additivated solder paste and a process to apply a reactive additive element for the control of the soldering temperature of electronic components on the reflow soldering method by the use of metallic particles deposited at the interface between the Printed Circuit Board pad, and the solder paste. The aim is to promote a transient melting reaction between the pad, the reactive additive element and the solder paste. Then the preliminary transient liquid phase reacts with the solder paste particles, and behaves as a catalyser for the solder alloy melting. The selective additive element addition, at the interface, allows a concentrated effect resulting in an enhanced degree of the initial melting temperature decrease at that zone. The technique is able to be applied on selected zones of a PCB. This way, during Surface Mount Devices reflow soldering, the PCB thermal gradients effects are minimized.