Thin films are disclosed that are suitable as dielectrics in IC's and for other similar applications. In particular, the invention concerns thin films comprising compositions obtainable by hydrolysis of two or more silicon compounds, which yield an at least partially cross-linked siloxane structure. The invention also concerns a method for producing such films by preparing siloxane compositions by hydrolysis of suitable reactants, by applying the hydrolyzed compositions on a substrate in the form of a thin layer and by curing the layer to form a film. In one example, a thin film comprising a composition is obtained by hydrolyzing a monomeric silicon compound having at least one hydrocarbyl radical, containing an unsaturated carbon-to-carbon bond, and at least one hydrolyzable group attached to the silicon atom of the compound with another monomeric silicon compound having at least one aryl group and at least one hydrolyzable group attached to the silicon atom of the compound to form a siloxane material.