Provided is a method of manufacturing a semiconductor device. The method includes providing a substrate in which a main area including a first cell area and a first peripheral area, and an edge area including a second cell area and a second peripheral area are defined, sequentially forming a mold layer, a supporter layer, a mask layer, and a preliminary pattern layer on the substrate, exposing the preliminary pattern layer to light to simultaneously form a first pattern and a second pattern on the mask layer of the first cell area and the second cell area, respectively, forming an etch stop layer on the second pattern and etching the mask layer using the etch stop layer and the first pattern to form a hole pattern in the mold layer and the supporter layer of the first cell area.