Jabil Inc.
Method and Apparatus for Stacking Printed Circuit Board Assemblies with Single Reflow

Abstract:

Disclosed herein are implementations of methods and devices for stacking printed circuit board (PCB) assemblies (PCBA) with a single reflow process which decreases impact on surface mount technology (SMT) component and solder joint reliability. A method includes transferring solder paste on to a bottom PCB and forming a bottom PCBA by placing SMT components on the bottom PCB. A middle PCB is stacked on the bottom PCBA and solder paste is transferred on to the middle PCB. A top PCB is stacked on the middle PCB and solder paste is transferred on to the top PCB. SMT components are placed on the top PCB to form a stacked assembly. The stacked assembly is reflowed in a single reflow so that all solder paste simultaneously or nearly simultaneously melts to bond SMT components to respective PCB boards and to bond respective PCBs to each other.