Chemical bonding structure of fluorinated amorphous carbon films prepared by electron cyclotron resonance plasma chemical vapor deposition

The a-C:F-x films with low dielectric constant has been studied,considering that they can be used for interlayer dielectric in ultra-large integrated circuits. These films were deposited by using electron cyclotron resonance plasma reactor with CHF3 and C6H6 mixture as source gas. The effects of mic rowave power,pressure and CHF3/C6H6 ratios on the film deposition rates hav e been investigated. The fluorocarbon and hydrocarbon radical species in th e plasma discharges were monitored by the optical emission spectra. The str uctural properties of the films were characterized by Fourier transform inf rared spectroscopy and X-ray photoelectron spectroscopy. A relationship bet ween the radical species in the discharge plasma and Lending structure of t he films is analysed. It demonstrates that CF2,CF and CH radicals play the important roles in the forming of films.