Young's Modulus Enhancement of Mesoporous Pure-Silica–Zeolite Low-Dielectric-Constant Films by Ultraviolet and Silylation Treatments

A Young's modulus as high as 10 GPa and a dielectric constant of 2.18 was obtained by post-deposition ultraviolet and silylation treatments of a mesoporous pure-silica–zeolite low-dielectric-constant (low- k ) film, while the dielectric constant value k after the treatments remained as low as 2.18. Spin-on zeolite suspension was calcined at 400 °C, and a silylation treatment using 1,3,5,7-tetramethylcyclotetrasiloxane (TMCTS) was then carried out. The film was irradiated with UV light with a wavelength of 254 nm followed by a second silylation treatment. After these treatments, an increased H–Si–O 3 stretching peak and reduced OH-related peak in the infrared absorption spectra were observed, indicating the formation of a thicker Si–O polymer network with methyl groups on the pore wall surface.