Investigation on the origin of dielectric constant evolution in films deposited from organosilicon molecules in microwave DECR plasma reactor

Low k dielectric thin films were elaborated in microwave distributed electron cyclotron resonance reactor by using organosilicon vapor and oxygen mixture as precursors. The dielectric constant evolution was studied as a function of the oxygen addition. Contribution of each permittivity component to the variation of the measured dielectric constant was carried out. Although the electronic and ionic polarizations have their influences on the value of the measured permittivity, they have not shown any effect on its evolution. A method to follow the dipolar polarization contribution to the dielectric constant is described. It suggests that both Si–O and Si–C polar groups present in the deposited films may have the predominant effect on the behavior of the dielectric constant.