Semiconductor device and electronic system

Abstract

A semiconductor device includes a lower stepped connection part at a first vertical level on a substrate, an upper stepped connection part at a second vertical level higher than the first vertical level on the substrate, a lower insulating block contacting each of the plurality of lower conductive pad parts at the first vertical level, an upper insulating block contacting each of the plurality of upper conductive pad parts at the second vertical level, an intermediate insulating film between the lower insulating block and the upper insulating block at a third vertical level between the first and second vertical levels, and a first plug structure extending into the lower stepped connection part, the intermediate insulating film, and the upper insulating block in the vertical direction, wherein a width of the first plug structure in the horizontal direction is greatest at the third vertical level.