Abstract: A high-resolution patterning method of a resist layer is disclosed by patternwise irradiation of the resist layer with electron beams utilizing a methanofullerene compound as the electron beam resist material, which is graphitized and made insoluble in an organic solvent by the electron beam irradiation in a dose of, for example, 1.times.10.sup.-4 C/cm.sup.2 or larger. The thus formed resist layer is highly resistant against dry etching to ensure utilizability of the method in the fine patterning work for the manufacture of semiconductor devices.