Effect of F- and CH-Doped on Dielectric Properties of SiCOH FilmsDeposited by Decamethylcyclopentasiloxane Electron Cyclotron ResonancePlasma

Abstract

We investigate the effect of CH-doped and F-doped on dielectricproperties of SiCOH films deposited by decamethylcyclopentasiloxane(DMCPS) electron cyclotron resonance plasma. The dielectric constantk is closely related to the configurations of films. For thefilms deposited only using DMCPS, the minimum k is as low as2.88. By adding CH4 in the precursor, the k value can bereduced to 2.45 due to the film density decreasing by incorporatinglarge size CHx groups. By adding CHF3 in the precursor,the k value can also be reduced to 2.48 due to the incorporationof the weak-polarization F atom. Thus the dielectric constant for SiCOHfilms depends on not only the film density but also the polarization ofatoms. By increasing the film density or by reducing the polarizationof atoms under the condition of a lower film density, the lowdielectric constant SiCOH films can be obtained.