US Patent 11257841 Three-dimensional semiconductor memory device

A three-dimensional semiconductor memory device including a stack structure including gate structures and first dielectric patterns alternately stacked, a vertical channel penetrating the stack structure, and a charge storage layer extending from between the vertical channel and the first gate structures to between the vertical channel and the first dielectric patterns. The gate structures include first gate structures having a top surface and a bottom surface facing each other and having different width. The charge storage layer includes first segments between the vertical channel and the first gate structures, and second segments between the vertical channel and the first dielectric patterns. A thickness of the first segments is greater than a thickness of the second segments. One of the width of the top surface and the width of bottom surface of each first gate structure is the same as that of a first dielectric pattern on the first gate structure.