Composition for forming porous film, porous film and method for forming the same, interlayer insulator film, and semiconductor device

摘要

The object of the invention is to provide a porous film having the dielectric constant of 2.2 or less and having practicable mechanical strength. This invention provides a porous film-forming composition comprising (A) and (B): (A) 100 parts by weight of a hydrolyzable silicon compound and/or a product resulting from hydrolysis condensation of silicon compound expressed by following formulae (1): R<1>aSiZ<1>4-a (1) wherein Z<1 >denotes a hydrolyzable group; R<1 >denotes a substituted or non-substituted monovalent hydrocarbon group; and a denotes an integer of 0 to 3; and (B) 0.1 to 20 parts by weight of a cross-linking agent comprising at least one cyclic oligomer which can generate silanol group(s) by heating and which is expressed by following formulae (3): {R<31>(H)SiO}d{R<32>(Z<3>)SiO}e (3) wherein R<31 >and R<32 >each denotes a substituted or non-substituted monovalent hydrocarbon group; Z<3 >denotes a group which can generate silanol by heating; and each d and e denotes an integer of 0 to 10, and a sum of d and e is greater than or equal to three.