Phase change materials

Phase change materials can be switched rapidly and repeatedly between amorphous and crystalline phases, which differ distinctly in their optical and electrical properties. This combination of properties is utilized to store information in rewritable optical storage media and in emerging phase change memory technology. This article describes the physical properties of phase change materials such as Ge 2Sb 2Te 5 and relates these properties to specific structural and bonding characteristics. Electrical conduction and switching, which are relevant for phase change memory operation, are explained from a physical perspective. Phase change memory device integration and technology development are discussed, including aspects of access device selection and integration. © 2012 Materials Research Society.