MULTI-BIT PHASE CHANGE MEMORY DEVICE

摘要

PURPOSE: A multi-bit phase change memory device is provided to implement a multi-bit phase change memory device which operates over two bits by using a phase change material. CONSTITUTION: A storage node(100) comprises a phase change material(10), a top electrode(20) and a bottom electrode(30). A heating element(40) applying heat to the phase change material is arranged between the bottom electrode and the phase change material. The phase change material has a first crystalline structure when supplying current pulse to heat the phase change material with over a first crystallization temperature. The phase change material has a second crystalline structure when supplying current pulse to heat the phase change material with over a second crystallization temperature.