Additive for resist and resist composition comprising same

An additive for resist represented by the following formula (1):

• wherein in the formula (1),
• R′, R″ and R′″ each independently represent a group selected from the group consisting of a hydrogen atom, a C1-C4 alkyl group, a halogen atom, and a C1-C4 haloalkyl group in which one of the hydrogen atoms of an alkyl group is substituted by a halogen atom;
• R1 and R2 each independently represent a hydrogen atom or a C1-C8 alkyl group;
• R3 represents a group selected from the group consisting of a hydrogen atom and functional groups represented by the following formulas (2) and (3):
• wherein in the formulas (2) and (3), R21 represents a hydrogen atom, or a hydroxyl-protecting group selected from the group consisting of a C1-C20 alkyl group, a (C1-C20 alkoxy)alkyl group, a C3-C30 cycloalkyl group, a formyl group, a (C1-C20 alkyl)carbonyl group, a (C3-C30 cycloalkyl)carbonyl group, a (C1-C20 alkyl)carboxyl group, and a (C3-C30 cycloalkyl)carboxyl group;
• R31 represents a hydrophobic group selected from the group consisting of a C1-C20 haloalkyl group, an organosilicon group and a C3-C20 hydrocarbon group, such that if R31 represents an organosilicon group, p represents 0, while if R31 represents a C1-C20 haloalkyl group or a C3-C20 hydrocarbon group, p represents 1;
• R22 and R32 each independently represent a group selected from the group consisting of a C1-C20 alkanediyl group, a C2-C20 alkenediyl group, a C1-C20 heteroalkanediyl group, a C2-C20 heteroalkenediyl group, a C3-C30 cycloalkenediyl group, a C3-C30 cycloalkenediyl group, a C2-C30 heterocycloalkanediyl group, and a C3-C30 heterocycloalkenediyl group;
• R23 and R33 each independently represent an acid-labile group selected from the group consisting of
• wherein Ra, Rb, Rc and Rd each independently represent a group selected from the group consisting of a C1-C20 alkyl group, a C3-C30 cycloalkyl group, a (C1-C10 alkyl)cycloalkyl group, a hydroxyalkyl group;
• a C1-C20 alkoxy group, a (C1-C10 alkoxy)alkyl group, an acetyl group, an acetylalkyl group, a carboxyl group, a (C1-C10 alkyl)carboxyl group, a (C3-C18 cycloalkyl)carboxyl group, and a C3-C30 heterocycloalkyl group, or adjacent groups may be bonded to each other to form a C3-C30 saturated or unsaturated hydrocarbon ring or a C2-C30 heterocyclic group;
• x represents an integer from 0 to 3;
• y represents an integer from 0 to 10;
• R4 represents a hydrophobic group selected from the group consisting of a C1-C20 haloalkyl group, an organosilicon group, and a C3-C20 hydrocarbon group;
• R5 represents a group selected from the group consisting of a hydrogen atom, a C1-C20 alkyl group, a C2-C20 alkenyl group, a C3-C30 cycloalkyl group, a C3-C30 cycloalkenyl group, a C6-C30 aryl group, a C1-C20 heteroalkyl group, a C2-C30 heterocyclic group, and combinations thereof;
• l, m, n and o respectively represent the proportions of corresponding repeating units in the main chain, such that l+m+n+o=1, while 0<l/(l+m+n+o)<0.9, 0.2<m/(l+m+n+o)<0.9, 0≦n/(l+m+n+o)<0.9, and 0≦o/(l+m+n+o)<0.9, provided that when R3 represents a hydrogen atom or a functional group represented by formula (2), n is not 0;
• and
• p represents an integer of 0 or 1.