Integration Challenges of Nanoporous Low Dielectric Constant Materials

The reliable integration of nanoporous low dielectric constant $(k)$ materials is challenging due to their vulnerability to delamination, cohesive cracking, and diffusion. We review selected reliability issues for the integration of nanoporous low-$k$ dielectrics regarding UV curing, diffusion, and damage evolution. Depth-dependent UV curing by the UV standing wave effect is presented. It is demonstrated that significant enhancement in fracture energies at both interfaces of low-$k$ films can be obtained by tailoring UV curing depth profiles and employing the underlying barrier as an optical spacer. The effects of nonionic surfactants on diffusion and damage evolution in nanoporous low-$k$ films are discussed.