Towards Universal Memories? Exploring the Potential of Phase Change Materials

Phase change media are among the most promising materials in information technology. There are already employed in rewriteable optical data storage, where the pronounced difference of optical and electrical properties between the amorphous and crystalline state is used for data storage. This unconventional class of materials is also the basis of a storage concept to replace flash memory. In this talk the relevant materials properties of phase change media will be discussed together with unsolved scientific issues and the potential of phase change based storage concepts. It will be demonstrated that only a small group of covalent semiconductors with octahedral coordination has the required unconventional property combination of high optical and electrical contrast and fast crystallization kinetics. The origin of this pronounced stoichiometry and structure dependence will be explained on the basis of advanced computations and a variety of experiments.