<p>A positive resist material for high energy-sensitive positive resists which can be developed in aqueous alkali solution comprises (A) a polyhydroxystyrene resin wherein some hydroxyl groups are substituted by t-butoxycarbonyloxy groups; (B) a solution blocking agent; and (C) an onium salt. The solution blocking agent contains at least one butoxycarbonyloxy group per molecule; the onium salt is bis(p-t-butylphenyl) iodinium trifluoromethylsulfonate (1): <CHEM> and the weight proportions of (A) , (B) , (C) are given by the relations: 0.07</=B </=0.40; 0.005 </=C </=0.15; 0.55</=A; and A + B + C = 1. As the resist has low absorption at the exposure wavelength of a KrF exima laser, a fine pattern having vertical walls is easily formed. <IMAGE></p>
申请公布号
EP0542523(B1)
申请公布日期
1999.03.10
申请号
EP19920310288
申请日期
1992.11.11
申请人
SHIN-ETSU CHEMICAL CO., LTD.;NIPPON TELEGRAPH AND TELEPHONE CORPORATION