Near-Room-Temperature Thermal Chemical Vapor Deposition of Poly(chloro-p-xylylene)/SiO2 Nanocomposites

A great necessity exists to reduce power consumption, cross-talk, and RC delay in ultra-large-scale integration (ULSI) devices to further improve their performance by replacing SiO2 with a low dielectric constant material. Recently, much work has been focused on chemical vapor deposition (CVD) polymer thin films; however, they often suffer from poor resistance to metal diffusion and undesirable dielectric anisotropy. To overcome these limitations, a thermal CVD nanocomposite consisting of poly(chloro-p-xylylene) (PPXC) and SiO2 was developed utilizing a recently developed near-room-temperature thermal CVD method to deposit SiO2. The composition of the nanocomposite thin films could be varied by increasing the vaporization temperature of the SiO2 precursor, diacetoxy-di-tert-butoxysilane. Since the composition could be varied, both the index of refraction and the dielectric constant of the nanocomposites could potentially be varied, in situ, to deposit a graded film to eliminate the diffusion problem. The ...