By generating supplementary patterns for EB data and using a system that corrects patten line widths, we improved the shape of a pattern formed on a photomask and the CD linearity. For the EB lithography system, trapezoidal and hammerhead supplementary patterns were applied in order to suppress the increase in EB data volume. As a result, it became possible to reduce the supplementary patterns generated to about 60 percent of the existing serif supplementary patterns. The formed pattern shapes were also equivalent. Since the laser lithography system requires bigger correction pattern shapes than the EB lithography system, triangle supplementary patterns were used. As a result, the corner round was improved with the number of patterns equivalent to that of existing rectangle supplementary patterns. For the CD-linearity, the CD correction amount was set for each line width from the experiment result. For 5 micrometers to 0.7 micrometers patterns on a photomask, a CD-linearity could be achieved within 40nm. We developed the system with above method, when the system is applied to 0.18 micrometers logic contact holes, the elapse time is 1.4 hours and the EB data file size is for 2.5 to 10.8 times the number of original patterns. We judged that it was in the practical level.