An integrated circuit device includes a memory including a memory cell insulation surrounding a memory stack and a memory cell interconnection unit, a peripheral circuit including a peripheral circuit region formed on a peripheral circuit board, and a peripheral circuit interconnection between the peripheral circuit region and the memory structure, a plurality of conductive bonding structures on a boundary between the memory cell interconnection and the peripheral circuit interconnection in a first region, the first region overlapping the memory stack in a vertical direction, and a through electrode penetrating one of the memory cell insulation and the peripheral circuit board and extended to a lower conductive pattern included in the peripheral circuit interconnection in a second region, the second region overlapping the memory cell insulation in the vertical direction.