Organically modified silicate films prepared by sol-gel techniques have been studied. The silicate structure has been modified by phenyl radicals. The films were prepared by cohydrolysis in various proportions of tetraethyloxysilane and phenyl triethoxysilane or diphenyl diethylhexyloxy diethoxydisiloxane. It is shown that phenyl radicals introduced into the silicate network reduce cross-linking in polymer structure, their density and hydroxyl contents. These provide low shrinkage, high cracking resistance, and low dielectric constant and loss tangent of phenyl-modified silicate films. Some questions of applications of such films in the process of planarization of multilevel interconnections are briefly discussed as well.