Aromatic hydrocarbon resin, underlayer film forming composition for lithography, and method for forming multilayer resist pattern

An aromatic hydrocarbon resin obtained by reacting an aromatic hydrocarbon represented by formula (1), an aldehyde represented by formula (2), and a phenol derivative represented by formula (3) in the presence of an acidic catalyst:

• wherein in formula (1), R represents hydrogen or an alkyl group having 1 to 4 carbon atoms;
• 1 and m each represent a number from 1 to 3;
• A represents a number from 0 to 2;
• and plural groups represented by R are the same or different from each other;
• wherein in formula (2), X represents hydrogen, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a cyclohexyl group, a hydroxyl group, a formyl group, or a carbonyl group;
• p and q each represent a number from 1 to 3;
• B represents a number from 0 to 2;
• and plural groups represented by X are the same or different from each other;
• and
• wherein in formula (3), Y and Z represent hydrogen, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or a cyclohexyl group;
• r and s each represent a number from 1 to 10;
• C represents a number from 0 to 2;
• and plural groups represented by Y and Z are the same or different from each other.