| abstract |
According to the present invention, a fine mask pattern can be formed on a substrate to be processed by a multilayer resist method, and a clean degree sufficient to process a substrate to be processed without damaging the substrate to be processed or a lower layer film, It is an object of the present invention to provide a pattern forming method capable of removing a film residue. A base polymer having a silicon-containing unit, a boron-containing unit and a phosphorus-containing unit, the total amount of the boron-containing unit and phosphorus-containing unit being 10 mol% or more, and the organic compound having two or more hydroxyl groups or carboxyl groups in one molecule, And a step of forming a BPSG film on the lower layer film by using a composition for forming a coating type BPSG film containing at least 25 parts by mass of an organic compound per 100 parts by mass of the polymer. |