Methods for forming a back side film stack and package structures thereof

Abstract

Embodiments of the present disclosure relate to methods for forming a film stack during fabrication or bonding process. The film stack according to present disclosure may reduce wet dip attacking to semiconductor substrate during bonding, such as bonding between an image sensor substrate and a logic device substrate. The film stack according to the present disclosure may be used to modulate stress and wafer warpage to improve bonding adhesion and device performance during various packaging schemes, such as CoWoS, SoIC, or the like. The film stack according to the present disclosure may be used to improve bonding process and device performance in both wafer-to-wafer bonding and die-to-die bonding.