The disclosure provides a double patterning technology to define peripheral patterns in a DRAM cell. Due to the consideration of line width, the peripheral pattern lines need to undergo two lithographic processes and two etch processes. The presence of additional photoresist patterns in the array region while fabricating peripheral patterns on the M0 layer can increase the stability of peripheral pattern lines. Peripheral pattern lines will not collapse after being subjected to the rinse of developing agent. Moreover, the photoresist coverage of patterns in the array region is not excessive, so the loading effect during etch processes is reduced and the occurrence of photoresist residues is avoided.