Currently, the most common semiconductor dielectric is silicon dioxide (SiO2), which has a dielectric constant of about 4.0. There is a substantial interest in materials with low dielectric constants that can replace SiO2-based insulators as inter layer dielectrics (ILD). This invention is directed to a new process for the preparation of low dielectric constant films. The sol-gel process employs a hyperbranched polycarbosilane precursor that is applied to a substrate by spin coating. The coating is cured at a suitable temperature to yield uniform, tough, solvent-resistant, and adherent polyorganosilicon films. The films are comprised of an organicinorganic organosilicon networked polymer material. The novel films consistently exhibit dielectric constants below 2.5 and as low as 1.8. The films exhibit thermal stability to at least 500 degrees C, greater solvent resistance, superior toughness, and hydrophobicity. Applications include a replacement for SiO2 based insulator as ILD.