Failure Analysis Case Study on Covalent Wafer bonding Delamination

Covalent wafer-to-wafer bonding is one of the package research fields that requires high quality SiO2 interface from 2 sides of Si wafers. Failure analysis on adhesion problem wafers is to understand the root cause of failures for process enhancement. In this paper, three different sample preparation methods have been used to analyze a covalent wafer-to-wafer bonding delamination issue that was captured in SAM. One simple and useful sample preparation method has been introduced in the paper. With this method, further analysis work can be carried out to provide full information of the defects.