Effect of ultraviolet cure on the interfacial toughness and structure of SiOC thin film on Si substrate

An experimental study on the adhesion of thin films was conducted for the ultraviolet (UV)-cured SiOC films on Si substrate by examining the mechanical energy balance during the indentation process combined with atomic force microscopy observation. The effect of UV cure on the interfacial delamination toughness and the structure of the SiOC films are discussed. The energy release rate of the SiOC film/Si substrate interfacial delamination increases with the increases in the time of UV curing, indicating that the indentation method is efficient to examine the adhesion of coating. As the UV curing time increases, the film thickness and the Si-CH3 bond structure decrease, whereas the SiO2 network structure develops and the mechanical properties of the film are improved. Furthermore, the energy release rate of SiOC film/Si interfacial delamination is well correlated in a proportional manner to the Young's modulus of the film.