Patent ID: 7736748

Claim:
An insulating-film-forming composition comprising an organic solvent and a hydrolysis-condensation product which is obtained by hydrolysis and condensation of a component (A) in the presence of a component (B), the component (A) being at least one silane compound selected from a group consisting of compounds shown by the following formulas (1) to (3) R a Si(OR 1 ) 4-a (1) wherein R represents a hydrogen atom, a fluorine atom, or a monovalent organic group, R 1 represents a monovalent organic group, and a represents an integer of 1 or 2, Si(OR 2 ) 4 (2) wherein R 2 represents a monovalent organic group, R 3 b (R 4 O) 3-b Si—(R 7 ) d —Si(OR 5 ) 3-c R 6 c (3) wherein R 3 to R 6 individually represent monovalent organic groups, b and c individually represent integers from 0 to 2, R 7 represents an oxygen atom, a phenylene group, or a —(CH 2 ) m — group (wherein m represents an integer from 1 to 6), and d represents 0 or 1, the component (B) being a polycarbosilane having a main chain structure shown by the formula —(Si—CH 2 ) x — (wherein x is an integer of two or more) and containing a structure shown by the following formula (4), a structure shown by the following formula (5), a structure shown by the following formula (6), and a structure shown by the following formula (7), wherein R 8 is selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxyl group, an alkoxyl group, and an acyloxyl group, wherein R 9 and R 10 are individually selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxyl group, an alkoxyl group, and an acyloxyl group, wherein R 11 to R 13 are individually selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxyl group, an alkoxyl group, and an acyloxyl group, wherein the component (B) contains in its molecule 5 to 20 mol % of the structure shown by formula (4), 5 to 20 mol % of the structure shown by formula (5), 20 to 50 mol % of the structure shown by formula (6), and 30 to 60 mol % of the structure shown by formula (7).