A method of manufacturing a semiconductor device includes: forming a first outer box and a second outer box on a wafer, providing a photoresist layer on the wafer; and by removing a portion of the photoresist layer, forming a photoresist pattern including a first opening and a second opening that are horizontally apart from each other, wherein the first opening defines a first inner box superimposed on the first outer box in a plan view, the second opening defines a second inner box superimposed on the second outer box in the plan view, and a horizontal distance between the first opening and the second opening is about 150 μm to about 400 μm.