INTEGRATED CIRCUIT DEVICE INCLUDING PERIPHERAL CIRCUIT AND CELL ARRAY STRUCTURES, AND ELECTRONIC SYSTEM INCLUDING SAME

An integrated circuit device includes; a peripheral circuit structure including a peripheral circuit, a first insulating layer covering the peripheral circuit, extension lines in the first insulating layer, and a first bonding pad in the first insulating layer, and a cell array structure including a conductive plate, a memory cell array below the conductive plate, a second insulating layer covering the memory cell array, a second bonding pad in the second insulating layer, a conductive via on the conductive plate, and a line connected to the conductive via. The first bonding pad contacts the second bonding pad, and the integrated circuit device further includes contact plugs electrically connecting the line to the extension lines.