The structures of low dielectric constant SiOC thin films prepared by direct and remote plasma enhanced chemical vapor deposition

Two structures of low dielectric constant (low-k) SiOC films were elucidated in this work. Low-k thin film by remote plasma mode was mainly composed of inorganic Si–O–Si backbone bonds and some oxygen atoms are partially substituted by CH3, which lowers k value. The host matrix of low-k thin films deposited by direct plasma mode, however, was mainly composed of organic C–C bonds and “M” and “D” moieties of organosilicate building blocks, and thus the low dipole and ionic polarizabilities were the important factors on lowering k value.