A negative pattern is formed to be transparent in the far ultraviolet region including the wavelength 193 nm of an ArF excimer laser and, despite its chemical structure having high dry etching, does not swell and has excellent resolution. An acid-catalyzed reaction is utilized wherein a .gamma.-hydroxy or .delta.-hydroxy carboxylic acid structure is partially or entirely converted to a .gamma.-lactone or .delta.-lactone structure. The negative pattern is developed with an aqueous alkali solution without swelling.