Semiconductor devices and methods of manufacturing semiconductor devices

Abstract

A method of manufacturing a semiconductor device includes forming a molded structure of stacked and alternating interlayer insulating layers and sacrificial layers on a lower structure, forming a hole through the molded structure, forming recess regions in the sacrificial layers of the molded structure, respectively, by removing a portion of the sacrificial layers, exposed through the hole, from side surfaces of the sacrificial layers, sequentially forming a preliminary blocking pattern and a charge storage pattern in each of the recess regions, sequentially forming a tunneling layer and a channel layer in the hole, forming trenches penetrating through the molded structure, such that the trenches extend in a line shape, removing the sacrificial layers exposed by the trenches, such that the preliminary blocking pattern is exposed, and oxidizing the preliminary blocking pattern, after removing the sacrificial layers, such that a blocking pattern is formed.