Composition for forming a coating type silicon-containing film, substrate, and patterning process

A composition for forming a coating type silicon-containing film, comprising

• one or more silicic acid skeletal structures represented by the formula (1) and one or more silicon skeletal structures represented by the formula (2), wherein the composition contains a coupling between units in the formula (2)
• wherein R1, R2, R3, R4, R5, and R6 each represent a hydrogen atom or an organic group having 1 to 30 carbon atoms, wherein a hydrogen atom(s) in the organic group may be substituted by a halogen atom(s);
• R7, R8, R9, R10, R11, and R12 each represent a methyl group, a phenyl group, or a hydroxyl group;
• m10, m11, m12, and m13 each represent a molar fraction in the silicic acid skeletal structure, and satisfy m10+m11+m12+m13=1, 0≦m10≦0.3, 0≦m11≦0.5, 0≦m12≦0.7, and 0<m13≦1;
• and m20, m21, m22, and m23 each represent a molar fraction in the silicon skeletal structure, and satisfy m20+m21+m22+m23=1, 0≦m20≦1, 0≦m21≦1, 0≦m22≦1, and 0≦m23≦1.