Characterization of 300 mm Low Temperature SiCN PVD Films for Hybrid Bonding application

Hybrid bonding or surface activated bonding is becoming the technology to manufacture higher density first-level interconnects by addressing pitch scaling difficulties of solder interconnects. One of the major challenges for dielectric bonding is to decrease the process temperature to be compatible with stacking schemes and device limitations. In this paper, we focus on both low temperature SiCN dielectric deposition and low temperature annealing temperatures (<250°C). Both physical vapor deposition (PVD) and plasma enhanced chemical vapor deposition (PECVD) of SiCN are investigated side by side. Films of various densities and stoichiometries are compared; pre and post activation hydrophilicity, post activation dangling bond densities are characterized to explain how to tune SiCN films for improved bond energy at low annealing temperatures.