Tailoring UV cure depth profiles for optimal mechanical properties of organosilicate thin films

Abstract

The adhesive and cohesive properties of organosilicate thin films are remarkably insensitive to UV curing. We demonstrate how to maximize these properties with UV standing waves together with an optical spacer underlying layer. Using a simulation of the UV cure profile through the film thickness, we demonstrate how a UV transparent SiN optical spacer layer can be selected to maximize curing at both sides of the organosilicate film with marked increases in interfacial fracture energy. On the contrary, a UV absorbing SiCN underlying layer resulted in significantly reduced UV intensities and small improvements of the interfacial fracture energies.