Semiconductor devices and data storage systems having a plurality of interconnected peripheral vias

Abstract

A semiconductor device includes: a first substrate; a second substrate including first and second regions; a stack structure in the first region and extending from the first region into the second region, the stack structure including interlayer insulating layers and gate layers, wherein the gate layers include gate pads having a step shape in the second region; a capping insulating layer at least partially covering the stack structure; an upper insulating layer on the stack structure and the capping insulating layer; a peripheral contact structure including a plurality of through-vias contacting the second substrate and spaced apart from the gate layers, and a peripheral contact pattern on the plurality of through-vias and connecting at least a portion of the plurality of through-vias to each other; a memory vertical structure; a support vertical structure; and a gate contact plug on the gate pads to be electrically connected to the gate pads.