Characterization of PVD SiCN dielectric for Hybrid Bonding Application

SiCN has gained attention as a dielectric material in hybrid bonding due to its excellent surface roughness after chemical mechanical polishing, copper diffusion barrier properties, and high bonding strength. Typically, SiCN deposition is carried out using plasma-enhanced chemical vapor deposition (PECVD), which involves high deposition and annealing temperatures exceeding 350°C. In this study, we investigate the potential of SiCN as a dielectric material for hybrid bonding by depositing it using physical vapor deposition (PVD). The PVD SiCN process is less complicated than the PECVD SiCN process and the deposition temperature is also lower. To evaluate PVD SiCN films, the effects of RF power and the Ar/N₂ ratio on the films were investigated. The deposition rate ranged from a minimum of 124.5 Å/min to a maximum of 428.3 Å/min, depending on the process conditions. The oxygen content in the SiCN thin films varied between 11% and 65% based on the deposition conditions, and the refractive index ranged from 1.5 to 1.9.