Impact of organic linking and terminal groups on the mechanical properties of self-assembly based low-k dielectrics

Abstract

The impact of terminal and linking organic groups on the mechanical stability of self-assembly based porous ultralow-k dielectrics was investigated by nanoindentation and four-point bending tests in conjunction with quantitative FTIR analysis. Using a set of six porous low-k dielectric films functionalized with alkyl- and aryl-based groups, we demonstrated that both elastic and fracture properties can be sensitive to the type of embedded linking or terminal groups. Based on the obtained correlations between the material composition and the mechanical properties, two approaches for improvement of fracture toughness in low-k dielectrics are proposed.