a method for making a mask in a process of fabricating a semiconductor device is disclosed , in which one database is classified into an sram block and a random logic block so that opc is separately performed for the sram block and the random logic block , thereby improving performance of the opc . the method includes dividing an input database into an sram block and a random logic block , respectively performing optical proximity correction for the sram block and the random logic block , and combining the sram block to the random logic block .