Radiation-sensitive composition

A radiation-sensitive composition comprising:

• a low-molecular-weight compound having one or more acid-dissociable groups which decompose by an action of an acid to enhance solubility in an alkaline developing solution and one or more radiation-sensitive acid-generating groups which generate an acid upon application of an active ray or radiation per molecule, and having a polystyrene-reduced number-average molecular weight (Mn) measured by gel permeation chromatography (GPC) of 500 to 4,000, wherein the low-molecular-weight compound is not obtained from chain growth polymerization of a monomer with an unsaturated bond;
• a solvent;
• and
• a radiation-sensitive acid-generator other than the low-molecular-weight compound,
• wherein a content of the low-molecular-weight compound is 80 mass % or more of 100 mass % of a total solid component of the radiation-sensitive composition, and
• wherein the low-molecular-weight compound is a compound shown by a following formula (1),
• wherein
• A represents
• an aliphatic group having 1 to 50 carbon atoms,
• an aromatic group having 6 to 50 carbon atoms,
• an organic group consisting of said aliphatic and said aromatic group, or
• a group having a valence which is a sum of l+m+n and which has two or more of the aliphatic group represented by A, the aromatic group represented by A, or the organic group represented by A;
• X represents —O—, —CH2C(═O)—O—, —C(═O)—O—, —OC(O)O—, or —Ar1—O—, wherein Ar1 represents a 1,4-phenylene group;
• R1 represents an acid-dissociable group which is a substituted or unsubstituted tertiary hydrocarbon group having 4 to 12 carbon atoms or a substituted or unsubstituted acetal group;
• Y represents —CH2—C(═O)—O—R2—, wherein R2 represents a substituted or unsubstituted methylene group or a substituted or unsubstituted alkylene group having 2 to 30 carbon atoms;
• l is an integer from 1 to 4;
• m is an integer from 1 to 3;
• n is an integer from 0 to 10;
• and
• Z is an organic group shown by a formula (2), a formula (3), a formula (4), or a formula (5) and, in a case where m is 2 or 3, the organic groups represented by Z are either a same or different,
• wherein
• M1+ in the formula (2) represents a monovalent onium cation;
• M2+ in the formula (3) represents a monovalent onium cation;
• R3 in the formula (3) and the formula (5) represents a substituted or unsubstituted alkyl group having 1 to 15 carbon atoms or a substituted or unsubstituted aryl group having 1 to 15 carbon atoms;
• P in the formula (4) represents a substituted or unsubstituted alkylene group having 2 to 10 carbon atoms or a substituted or unsubstituted arylene group having 2 to 10 carbon atoms;
• and
• Q in the formula (5) represents a group shown by a formula (6), a formula (7), or a formula (8),
• wherein an amount of the radiation-sensitive acid generator is from 0.1 to 10 parts by mass for 100 parts by mass of the low-molecular-weight compound.