SEMICONDUCTOR MEMORY DEVICES

Semiconductor memory devices include a first storage layer and a second storage layer, each of which includes at least one array, and a control layer for controlling access to the first storage layer and the second storage layer so as to write data to or read data from the array included in the first storage layer or the second storage layer in correspondence to a control signal. A memory capacity of the array included in the first storage layer is different from a memory capacity of the array included in the second storage layer.