Development of Cr-based attenuated phase-shift mask process for 0.18-μm device generation

Making attenuated phase shift masks for KrF excimer laser lithography is going to be on the mass production stage for the 0.18 micrometer critical hole and line layers. Here, key issues are phase controllability, critical dimension (CD) control on the mask and mask defect repair technique. To get a sufficient mask CD controllability, we use a chemically amplified negative EB resist with a 10 kV electron beam system. For a better phase mean to target control, we have applied Chrome-based attenuated phase shift blanks. The phase angle adjusted using post process of quartz etching after pattern defect inspection. To guarantee the CD error of repaired patterns on wafer, preliminary investigation of printability with repaired mask patterns is presented.