Composition for resist underlayer film formation, resist underlayer film and forming method thereof, patterned substrate-producing method, and compound

A patterned substrate-producing method comprising:

• applying a composition for resist underlayer film formation comprising a compound represented by formula (1) and a solvent, directly or indirectly on an upper face side of a substrate to form a coating film;
• heating the coating film to form a resist underlayer film;
• forming a resist pattern on an upper face side of the resist underlayer film;
• and
• etching the substrate using the resist pattern as a mask,
• Ar1Ar2R1)n)m (1)
• wherein, in the formula (1),
• Ar1 represents a 1,3,5-triazinetriyl group;
• m is an integer of 3;
• Ar2 is a group bonding to a carbon atom of the 1,3,5-triazinetriyl group represented by Ar1 and represents an aromatic carbocyclic group having 6 to 20 ring atoms and having a valency of (n+1);
• n is an integer of 0 to 12,
• wherein a plurality of Ar2s are identical or different from each other, and a plurality of n's are identical or different from each other;
• and
• R1 represents a monovalent organic group having 1 to 20 carbon atoms, a hydroxy group, a halogen atom, or a nitro group,
• wherein the number of R1s in the compound is three or more,
• wherein at least three R1s each represent an organic group comprising at least one multiple bond or an organic group comprising an epoxy group, the at least one multiple bond being selected from the group consisting of:
• an ethylenic carbon-carbon double bond;
• a carbon-carbon triple bond;
• a carbon-nitrogen double bond;
• a carbon-nitrogen triple bond;
• and a carbon-oxygen double bond, and
• wherein in a case in which R1 is present in a plurality of number, a plurality of R1s are identical or different from each other.

A compound represented by formula (1′):

• Ar1Ar2R1)n)m (1′)
• wherein, in the formula (1′),
• Ar1 represents a 1,3,5-triazinetriyl group;
• m is an integer of 3;
• Ar2 is a group bonding to a carbon atom of the 1,3,5-triazinetriyl group represented by Ar1 and represents an aromatic carbocyclic group having 6 to 20 ring atoms and having a valency of (n+1);
• n is an integer of 0 to 12,
• wherein a plurality of Ar2s are identical or different from each other, and a plurality of n's are identical or different from each other;
• and
• R1 represents a monovalent organic group having 1 to 20 carbon atoms, a hydroxy group, a halogen atom, or a nitro group,
• wherein the number of R1s in the compound is three or more,
• wherein at least three les each represent an organic group comprising at least one multiple bond or an organic group comprising an epoxy group, the at least one multiple bond being selected from the group consisting of:
• an ethylenic carbon-carbon double bond;
• a carbon-carbon triple bond;
• a carbon-nitrogen double bond;
• a carbon-nitrogen triple bond;
• and a carbon-oxygen double bond, and
• wherein in a case in which R1 is present in a plurality of number, a plurality of R1s are identical or different from each other.