Synthesis and Characterization of Nano-Porous Oxidized Silica Film with Low Dielectric Constant

Abstract

A route to prepare nano-porous oxidized silica film using plasma-enhanced chemical vapor deposition (PECVD) is reported in this paper. Taking hexamethyldisiloxane (HMDSO) as the monomer, doping with O2, while adding a small amount of ether, the oxidized silica film is synthesized on the glass substrate using glow discharge. At last, the film is heated to produce more pores to reduce its dielectric constant. Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and atomic force microscopy (AFM) are used to characterize the film; the refractive index is measured by the ellipsometer; and then, the dielectric constant of the films is calculated. The results show that the films with dielectric constant smaller than 2.0 can be acquired by adjusting the proportion of HMDSO and O2, discharge time, and discharge power.