Patent ID: 7060361

Claim:
A silica-based organic film obtained by a method comprising: applying a coating solution on a target material to form a coating film, the coating solution containing a reaction product obtained by hydrolyzing, in an organic solvent in the presence of an acid catalyst, at least one first alkoxysilane compound selected from the group consisting of compounds represented by general formula (I): R 1 2 Si(OR 2 ) 2 (I) wherein R 1 represents an alkyl group having 1 to 4 carbon atoms or a phenyl group, and R 2 represents an alkyl group having 1 to 4 carbon atoms, and compounds represented by general formula (II): R 3 Si(OR 4 ) 3 (II) wherein R 3 represents an alkyl group having 1 to 4 carbon atoms or a phenyl group, and R 4 represents an alkyl group having 1 to 4 carbon atoms, and baking the coating film in an atmosphere having an oxygen concentration of 1000 ppm or less, and at a temperature from 680° C. to 750° C. to form a film, wherein an etching rate of the silica-based organic film in wet etching using hydrofluoric acid having a concentration of 0.5% by weight at 25° C. is 60 angstroms/min or less, and wherein an organic group content, which is represented as a ratio of the total of a peak area of SiR 1 and a peak area of SiR 3 to a peak area of Si—O—Si in a spectrum obtained by measuring an infrared absorption spectrum of the film, is 0.01 or more.