A polymer, an organic layer composition, and a method of forming patterns, the polymer including a structural unit represented by Chemical Formula 1 or Chemical Formula 2:

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A polymer, an organic layer composition, and a method of forming patterns, the polymer including a structural unit represented by Chemical Formula 1 or Chemical Formula 2:

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An actinic ray-sensitive or radiation-sensitive resin composition includes a resin (A) containing a repeating unit represented by General Formula (4) and a crosslinking agent (C) containing a polar group, in which the crosslinking agent (C) is a compound represented by General Formula (1) or a compound in which two to five structures represented by General Formula (1) are connected via a linking group or a single bond represented by L.sub.1 in General Formula (3). ##STR00001##

An actinic ray-sensitive or radiation-sensitive resin composition includes a resin (A) containing a repeating unit represented by General Formula (4) and a crosslinking agent (C) containing a polar group, in which the crosslinking agent (C) is a compound represented by General Formula (1) or a compound in which two to five structures represented by General Formula (1) are connected via a linking group or a single bond represented by L.sub.1 in General Formula (3). ##STR00001##

A polymer comprising recurring units derived from a polymerizable monomer having two structures of hydroxyphenyl methacrylate having a hydroxy group substituted with an acid labile group is used as base resin in a positive resist composition, especially chemically amplified positive resist composition. The resist composition forms a resist film which is processed by lithography into a pattern of good profile having a high resolution, minimal edge roughness, and etch resistance.

A polymer comprising recurring units derived from a polymerizable monomer having two structures of hydroxyphenyl methacrylate having a hydroxy group substituted with an acid labile group is used as base resin in a positive resist composition, especially chemically amplified positive resist composition. The resist composition forms a resist film which is processed by lithography into a pattern of good profile having a high resolution, minimal edge roughness, and etch resistance.

A polymer comprising recurring units derived from a polymerizable monomer having two structures of hydroxyphenyl methacrylate having a hydroxy group substituted with an acid labile group is used as base resin in a positive resist composition, especially chemically amplified positive resist composition. The resist composition forms a resist film which is processed by lithography into a pattern of good profile having a high resolution, minimal edge roughness, and etch resistance.

A polymer comprising recurring units derived from a polymerizable monomer having two structures of hydroxyphenyl methacrylate having a hydroxy group substituted with an acid labile group is used as base resin in a positive resist composition, especially chemically amplified positive resist composition. The resist composition forms a resist film which is processed by lithography into a pattern of good profile having a high resolution, minimal edge roughness, and etch resistance.