A novel role for SiCN to suppress H2O outgas from TEOS oxide films in hybrid bonding

The novel use of SiCN underneath TEOS oxide as a bonding surface in the wafer bonding of Backside-illuminated (BSI) sensor is proposed and the mechanism of void control by SiCN is clarified. In general, high-temperature processing results in generating voids between the wafer interfaces after bonding due to the release of high-pressure H
2
O contained in TEOS. In the proposed mechanism, the SiCN exposed to high-temperature H
2
O is oxidized thereby preventing the emission of high-pressure H
2
O gas. This paper analyzes the role of SiCN in this mechanism.