Ultralow-Temperature Deposition and Enhanced Bonding of SiCN Films for Advanced 3-D Integration

This study explores the potential of SiCN films as a low-temperature alternative to SiO₂ insulators for hybrid bonding in 3-D integration. SiCN films were deposited at 180C and 350C to investigate the effects of deposition temperature and composition on bonding performance. By optimizing precursor flow rates, we tailored the film properties, enhancing Si dangling bonds crucial for bonding. To achieve ultralow-temperature bonding below 100° C, O₂ plasma and potassium hydroxide (KOH) surface treatments were employed, significantly improving bonding interfaces by increasing Si-OH groups on the surface. Our results demonstrate that SiCN films deposited at low temperatures can achieve bonding characteristics comparable to those of high-temperature films. The enhanced bonding performance is attributed to surface treatments that mitigate hydrogen content and promote Si-OH formation. The low-temperature bonding capabilities of SiCN contribute to reducing thermal budgets, preventing device degradation, and advancing 3-D integration and hybrid bonding technologies for next-generation semiconductor applications.