| abstract |
The present invention relates to a polymer compound having a weight average molecular weight ranging from 1,000 to 500,000, which contains a repeating unit of (meth) acrylate in which a hydrogen atom of a carboxyl group is substituted with an acid labile group having a cyclic structure, a novolac resin of dihydroxynaphthalene And a photo acid generator. The positive resist material of the present invention is excellent in resolution and landing characteristics and adhesion on a highly reflective stepped substrate, has high resolution, and has favorable pattern shape and edge roughness after exposure. Therefore, a positive resist material, particularly, a chemically amplified positive resist material, which is particularly suitable as a material for forming a fine pattern of a photomask for ultra LSI fabrication or EB imaging, can be obtained. |