Abstract: A method for cleaning a semiconductor substrate includes peeling and dissolving an adhesive layer formed on a semiconductor substrate using a peeling and dissolving composition, in which the peeling and dissolving composition contains: a component [I]: a quaternary ammonium salt; a component [II]: an amide-based solvent; and a component [III]: a solvent represented by the following Formula (L): L1-L3-L2??(L) where L1 and L2 each independently represents an alkyl group having 2 to 5 carbon atoms, and L3 represents O or S.

Abstract: A polyrotaxane of high heat resistance contains a linear molecule, a cyclic molecule enclosing the linear molecule such that the cyclic molecule is skewered with the linear molecule, and 5 blocking groups disposed at both ends of the linear molecule. The cyclic molecule contains an aromatic ring having, on a side chain, a phenolic hydroxyl group. The polyrotaxane can be produced by dissolving, in a methanol-containing solvent, a linear molecule and a cyclic 10 molecule containing an aromatic ring having, on a side chain, a phenolic hydroxyl group, to yield a pseudo polyrotaxane in which the cyclic molecule encloses the linear molecule such that the cyclic molecule is skewered with the linear molecule; and dissolving the pseudo polyrotaxane and a blocking group 15 material in a solvent, to dispose blocking groups at both ends of the linear molecule.