PCB Assembly System Set-Up for PoP
This paper will explore the challenges and solutions of PoP assembly for the SMT assembly system.
DOWNLOAD
Authored By:
Gerry Padnos
Juki Automation Systems
Morrisville, NC 27560 USA
Summary
Traditional SMT assembly is a two dimensional process. Each component is placed on the same horizontal plane in different X and Y locations. In Package on Package (PoP) assembly, components are placed on successively higher layers. Since components are stacked on top of each other, traditional solder paste printing cannot be used. The typical SMT method to print solder paste can only be used to print paste on a single horizontal plane.
For PoP, the components that are placed on top of existing components need to have flux or special dipping solder paste applied at the time of assembly. This paper will explore the challenges and solutions of PoP assembly for the SMT assembly system.
Conclusions
The ability to assemble PoP devices requires two main changes from the standard SMT assembly process: application of flux to some or all components and the ability to stack components on top of each other.
While these two requirements are new to the SMT assembly process, the technologies and hardware have been around for many years and are well established. There are several possible assembly processes that can be used depending on the specific application. Adding the ability to assemble PoP devices is not difficult after understanding the basic requirements for PoP assembly as well as the specific application requirements.
Initially Published in the IPC Proceedings
|
