LOW TEMPERATURE FUSION BONDING WITH HIGH SURFACE ENERGY USING A WET CHEMICAL TREATMENT

摘要

Described is a wet chemical surface treatment involving NH₄OH that enables extremely strong direct bonding of two wafer such as semiconductors (e.g., Si) to insulators (e.g., SiO₂) at low temperatures (less than or equal to 400° C.). Surface energies as high as ~4835±675 mJ/m² of the bonded interface have been achieved using some of these surface treatments. This value is comparable to the values reported for significantly higher processing temperatures (less than 1000° C.). Void free bonding interfaces with excellent yield and surface energies of ~2500 mJ/m² have also be achieved herein.