The chemical-mechanical relationship of the SiOC(H) dielectric film

We propose an atomic simulation technique to understand the chemical-mechanical relationship of amorphous/porous silica based low-dielectric (low-k) material (SiOC(H)). The mechanical stiffness of the low-k material is a critical issue for the reliability performance of the IC backend structures. Due to the amorphous nature of the low-k material which has till now unknown molecular structure, a novel algorithm is required to generate the molecular structure. The molecular dynamics (MD) method is used as the simulation tool. Moreover, to understand the variation of the mechanical stiffness and density by the chemical configuration, sensitivity analyses have been performed. A fitting equation based on homogenization theory is established to represent the MD simulation results. The trends which are indicated by the simulation results exhibit good agreements with experiments from literature. Moreover, the simulation results indicate that the slight variation of the chemical configuration can induce significant change of the mechanical stiffness (over 80%) but not the density.