A multibit phase change memory device structured such that a plurality of
individual phase change memory devices are aligned in a plan area or
vertically, and a method of driving the same are provided. The multibit
phase change memory device includes a phase change material layer having
a plurality of contact portions being in contact with a heating
electrode, and having a plurality of active regions, each active region
forming a unit phase change memory device. The phase change material
layer may be composed of one material layer in which the plurality of
active regions are aligned in plural arrays. Alternatively, the phase
change material layer may be composed of a plurality of phase change
material layers in which one or plural active regions are respectively
aligned in one array. The plurality of phase change material layers may
be disposed in a same level of a plan area, or the plurality of phase
change material layers may be respectively disposed on different plan
areas in a same vertical line.