PURPOSE: To provide a novel photoresist composition used for lithography by the use of ultraviolet ray and particularly to provide the photoresist composition capable of lithography of submicron by far ultraviolet ray (DUV) and free from the distortion of an image even at the time of high temp. treating such as plasma etching executed at above 170°C, sputtering or ion implantation.

CONSTITUTION: The photoresist composition consists of an alkali soluble polymer and a bisazide sensitizer of sufficient quantity to cross-link the alkali soluble polymer by irradiation with ultraviolet and the alkali soluble polymer is composed of indene and maleimide or a polymerizing component of naphtha oil, which is composed mainly of indene and contains (A) 70-99wt.% indene, (B) 0.5-29.5wt.% styrene and (C) 0.5-29.5wt.% one kind or two or more kind selected from a group composed of α-methyl styrene, methyl styrene, dimethyl styrene, trimethyl styrene, methyl indene, coumarone and dicyclopentadiene, and maleimide.