Semiconductor device and electronic system including the same

Abstract

Semiconductor devices are provided. The semiconductor devices may include a peripheral circuit structure, a memory cell block arranged on the peripheral circuit structure and including strings, each of which includes a lower select transistor, memory cell transistors, and an upper select transistor connected in series and stacked in a vertical direction, and bit lines on the memory cell block. The bit lines may include a first bit line electrically connected to first to third strings of the strings. The lower select transistors of the first to third strings include first to third lower select gate electrodes, respectively. The second lower select gate electrode may be arranged at a different vertical level from the first lower select gate electrode, and the third lower select gate electrode may be arranged at the same vertical level as the first lower select gate electrode.