Study on the Manufacturability of X Dimension Fan Out Integration Package with Organic RDLs (XDFOI-O)

Abstract

The concept of chiplet was proposed in the post- Moore era. How to layout the multiple chips with different processes and sizes in the package structure is a problem that needs to be considered as different layouts may significantly affect the manufacturability during the packaging process. XDFOI-O is a 2.5D organic interposer structure with a significant coefficient of thermal expansion mismatch in it. Different layouts may cause excessive stress concentration in the package structure, as well as large wafer warpage, which can affect the normal operations of the production line. Stress accumulation on specific chiplet during the wafer thinning process is another manufacturability problem, leading to chip cracking. Prospective finite element analysis can be applied to evaluate the various layouts. In simulation work, different placement processes of dummy chips as stiffeners, as well as different chiplet thicknesses and underfill coverage, can be used as factors for simulation studies, thereby making a reference for further chiplet package design.