Development Of Wafer-Level Compression Molding System With The 5-Point Toggle Mechanism
In recent years, a wafer-level molding process is used as an important step in the semiconductor packaging process. In various molding methods, the compression molding process studies are being actively investigated. To perform the compression molding process with a maximum 12inch wafer size, this process must be performed to be able to have a press load of 100tons and keep the flatness of the product is also less than ±10um. In order to apply a high load in a semiconductor package manufacturing environment, the mechanical loading method is considered rather than hydraulic. In this paper, we developed a system by applying a toggle pressing method for performing the molding process. In addition, we developed a compression-mold having a high precision to fit the flatness of the product within ±10um. The compression-mold has been developed by applying a technique for adjusting a high-precision flatness and the non-uniformity temperature control of the upper and lower dies. The molding-process is carried out in an 8-inch by applying a granular-EMC in order to verify the performance of the developed system. And we can get the result that the flatness of the molded specimens is 25-35um. From the analysis of results, this flatness is combined with war page of substrate and molded materials (EMC, device, molding tape). To evaluate the mechanical precision of the developed compression-molding system, the research and development on the effect of thermal expansion coefficient and the optimum process condition will be required.
Keywords- Wafer-Level Compression Molding Process, Fan Out Wafer Level Package, Toggle Mechanism, Compression Mold Module, Granular-EMC.