Fan out Technology

    The functionality integrated in the 2.5D or 3D multi chip packaging has become increasingly diverse and crucial for specific applications. Current research and design efforts will continue to extend the breadth of the system in package composition, the next new technology could likely be the most important things to connect between dies in the package.

    In 2016, TSMC introduced the Integrated FanOut Technology(InFO), was used for Apple A10 application processor for Iphone 7. It was the first commercial InFO product in the market. InFO package is located at the bottom and memory package is stacked on top, so it makes package on package. In InFO package, die is surrounded by molding compound. Typically Fan Out uses liquid mold compound instead of solid pellet shape. At the bottom of InFO, there is redistribution layer(RDL) instead of package substrate. Therefore, there is no package substrate because it is Fan Out. When it uses through InFO via to connect bottom for application processor and top package for memory. There are some technological innovations in TSMC InFO in 2016 for Applie iphone. It was the first wafer level fan out package by foundry and applied to high volume manufacturing. Usually packaging is provided by OSAT, outsourcing assembly and test providers. But TSMC is foundry which makes chips based on customer design. Its package size is larger than 10x10mm with 8x8mm die size, and it is for high I/O device, application in smart phone