Patent ID: 8062414

Claim:
A coating liquid for forming an amorphous silica-based coating film with a low dielectric constant on a substrate, said coating liquid comprising: a silicon compound obtained by hydrolyzing tetraalkyl ortho silicate (TAOS) and alkoxysilane (AS) represented by the following general formula (I) in the presence of purified tetraalkyl ammonium hydroxide (TAAOH) without containing impurities comprising compounds of alkali metal elements and halogen group elements, a molar ratio of TAOS:AS being in a range of 6/4 to 2/8 and a molar ratio of TAAOH:(TAOS+AS) being in a range of 1/10 to 7/10, and said purified tetraalkyl ammonium hydroxide (TAAOH), X n Si(OR) 4-n (I) wherein X indicates a hydrogen atom, a fluorine atom, or an alkyl group, a fluorine-substituted alkyl group, an aryl group or a vinyl group each having 1 to 8 carbon atoms; R indicates a hydrogen atom, or an alkyl group, an aryl group or a vinyl group each having 1 to 8 carbon atoms; and n is an integral number from 1 to 3.