Semiconductor device and electronic system including the same

Abstract

Disclosed are a three-dimensional semiconductor memory device and an electronic system including the same. The device includes a substrate, a cell array structure provided on the substrate to include a plurality of stacked electrodes spaced apart from each other, an uppermost one of the electrodes being a first string selection line, a vertical channel structure provided to penetrate the cell array structure and connected to the substrate, a conductive pad provided in an upper portion of the vertical channel structure, a bit line on the cell array structure, a bit line contact electrically connecting the bit line to the conductive pad, and a cutting structure penetrating the first string selection line. The cutting structure penetrates a portion of the conductive pad. A bottom surface of the bit line contact includes first and second bottom surfaces in contact with the conductive pad and the cutting structure, respectively.