SEMICONDUCTOR DEVICE

A semiconductor device including a peripheral circuit structure; and a cell structure stacked on the peripheral circuit structure and including a cell region, a connection region, and a peripheral circuit connection region, wherein the cell structure includes gate electrodes spaced apart from one another in a vertical direction in the cell region; a channel structure extending in the vertical direction through the gate electrodes, in the cell region, and including a first end and a second end opposite to the first end, the first end being proximate to the peripheral circuit structure; an insulating wall extending in the vertical direction at a boundary between the cell region and the connection region; and a common source layer connected to the second end of the channel structure in the cell region and having a portion arranged on a sidewall of the insulating wall.