Transmission Fourier Transform Infra-red Spectroscopy Investigation of Structure Property Relationships in Low-k SiO x C y :H Dielectric Thin Films

In order to understand the structure property relationships for inorganic low dielectric constant (i.e. low-k) materials, transmission Fourier Transform-Infrared (FTIR) spectroscopy has been utilized to study the local bonding structure in various plasma enhanced chemically vapor deposited low-k materials in the SiO x C y :H phase diagram. The FTIR measurements were combined with additional mechanical, electrical, and optical property measurements to elucidate the structure property relationships for these materials. The combined measurements show that increased incorporation of terminal methyl bonding results in a decrease in network bonding that manifests itself in a reduction in mass density, dielectric constant, refractive index, Young’s modulus and many other important material properties.