Effects of precursor aging and post-deposition treatment time on photo-assisted sol–gel derived low-dielectric constant SiO2 thin film on Si

In this paper, we have reported the results of sol–gel derived low dielectric constant SiO2 treated with UV light as a function of precursor aging time and post-deposition UV exposure time. Filmetrics, Fourier-transform infrared, and scanning electron microscope were employed to characterize the films. Precursor aged for the longest time (4 days) has demonstrated the lowest refractive index, which can be related to reduction of dynamic dielectric constant (ke). However, when the UV exposure time increased, the ke value also increased. These observations have been explained in the text.