Composition for forming organic film, substrate for manufacturing semiconductor device, method for forming organic film, patterning process, and polymer

A composition for forming an organic film, comprising:

• a polymer having a partial structure shown by the following general formula (1) as a repeating unit;
• and
• an organic solvent,
• wherein each of AR1 and AR2 represents a benzene ring or a naphthalene ring which optionally have a substituent;
• W1 represents any shown by the following general formulae (2), (4), and (6), and the polymer optionally contains two or more kinds of W1;
• and W2 represents a divalent organic group having 6 to 80 carbon atoms and at least one or more aromatic rings,
• wherein AR3, AR4, and AR5 each represent a benzene ring or a naphthalene ring which optionally have a substituent, and aromatic rings of AR3 and AR4, or AR4 and AR5, optionally form a bridge structure via carbon atoms to which hydrogen atoms have been bonded on the aromatic ring;
• and Y represents a substituent shown by the following general formula (3),
• Y═—R3≡R4 (3)
• wherein R3 represents a single bond or a divalent organic group having 20 or fewer carbon atoms;
• and R4 represents hydrogen or a monovalent organic group having 20 or fewer carbon atoms,
• wherein AR6 and AR7 each represent a benzene ring or a naphthalene ring which optionally have a substituent;
• n1 represents 0 or 1, when n1=0, AR6 and AR7 form no bridge structure between aromatic rings thereof via Z, and when n1=1, AR6 and AR7 form a bridge structure via Z;
• Z represents a single bond or any in the following general formula (5);
• and Y represents a substituent shown by the general formula (3),
• wherein AR8 represents a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, or a pyrene ring;
• Y represents a substituent shown by the general formula (3);
• and n2 and n3 represent integers satisfying relations of 0≤n2≤4, 0≤n3≤4, and 1≤n2+n3≤4.