hydroxy carboxylic acid structure synthesized in synthesis example 1 and 2 parts by weight of an acid generator triphenylsulfonium triflate were dissolved in 600 parts by weight of cyclohexanone and the solution was filtered through a teflon filter having a pore diameter of 0 20 u03bcm to prepare a resist solution the resist solution was applied by spin coating onto a silicon substrate which had been treated with hexamethyldisilazane and the coating was heat treated at 100c for 2 min thereby forming a 0 54 u03bcm thick resist film the absorption spectrum of this film was measured with an ultraviolet visible spectrophotometer as a result it was found that the transmittance at 193 nm was 25 the substrate coated with the above resist was placed in an apparatus for an exposure experiment wherein the interior of the apparatus had been purged with nitrogen and a levenson type phase shifting mask formed on a quartz plate was brought into intimate contact with the coated substrate an arf excimer laser was applied through the mask followed by post baking at 100c for 2 min the resist film was immersed in an aqueous tetramethylammonium hydroxide solution concentration 0 113 wt at 23c as a.