Further, in the semiconductor memory device 1, the column sections 13a are provided in the back gate electrode film 13. Consequently, in the process shown in FIGS. 7A to 7C, when the sacrificial member 60 is removed from the hollow 65, the column sections 13a can support the hollow 65. Therefore, it is possible to prevent the hollow 65 from collapsing. Since the column sections 13a are periodically arrayed, it is possible to more surely support the hollow 65. Further, the column sections 13a are disposed relatively sparsely. The distance between the columns sections 13a adjacent to each other is longer than the distance between the silicon pillars 28 adjacent to each other. Consequently, in the process shown in FIGS. 7A to 7C, the width of a narrowest portion of the hollow 65 is not smaller than the interval between the memory holes 64 adjacent to each other. As a result, in the process shown in FIGS. 8A to 8C, when polysilicon is embedded in the hollow 65 to form the mesh-like connecting member 25, it is possible to surely embed the polysilicon.
