EVG LayerRelease Technology ; Key Innovations in Carrier Systems: Addressing D2W and W2W Stacking Requirements
EVG's IR LayerRelease Technology is a fully front-end-compatible layer release technology that features an infrared (IR) laser that can pass through silicon, which is transparent to the IR laser wavelength. Coupled with the use of specially formulated inorganic layers, this technology enables an IR laser-initiated release of any ultra-thin film or layer from silicon carriers with nanometer precision.
IR LayerRelease Technology enables silicon wafer carriers in advanced packaging processes such as Fan-out Wafer-level Packaging (FoWLP) using mold and reconstituted wafers as well as interposers for 3D Stacked ICs (3D SIC). At the same time, its compatibility with high-temperature processes enables completely novel process flows for 3D IC and 3D sequential integration applications – enabling hybrid and fusion bonding even of ultra-thin layers on silicon carriers, thereby revolutionizing 3D and heterogeneous integration as well as material transfer in next-generation scaled transistor designs.
In 3D integration, carrier technologies for thin-wafer processing are key to enabling higher performance systems with increasing interconnection bandwidth. Glass carriers have become an established method for building up device layers through temporary bonding with organic adhesives, using an ultraviolet (UV) wavelength laser to dissolve the adhesives and release the device layers, which are subsequently permanently bonded onto the final product wafer. However, glass substrates are difficult to process with semiconductor fab equipment that have been designed primarily around silicon, and that require costly upgrades to enable glass wafer processing. In addition, organic adhesives are generally limited to processing temperatures below 300°C, which limits their use to back-end processing.
Enabling silicon carriers with inorganic release layers avoids these temperature and glass carrier compatibility issues. In addition, the nanometer precision of IR laser-initiated separation opens upthe possibility of processing extremely thin device wafers without changing processes of record. Subsequent stacking of such thin device layers enables higher bandwidth interconnects and opens up new opportunities to design and segment dies for next-generation high-performance systems.