Demonstration of Phase Change Memories devices using Ge2Sb2Te5 films deposited by Atomic Layer Deposition

Phase change memory technology is considered as one of the most promising resistive memory solution. One issue, however, is the high electrical current required to reset the information. Indeed large energies are mandatory for amorphization of the crystalline phase change material. It has been demonstrated that energies can be highly decreased by reduction of the active volume and confinement of the phase change material. To do so, phase change materials deposition route with high filling capacity is needed. Atomic Layer Deposition (ALD) is well known for its high conformity. However, such a process is still a challenge for phase change materials such as Ge_xSb_yTe_z (GST). In this work, (i) ALD GST films are processed and characterized and (ii) realisation of phase change memory devices using ALD GST is demonstrated on 200mm wafers.