TRANSIENT PHASE CHANGE ANALYSIS OF SCALING IN PHASE CHANGE DEVICES

Abstract

Phase Change Random Access Memory (PCRAM) is one of the next-generation nonvolatile memories with the most potential. A transient measurement method has been developed to link the transient phase change effect to its crystallization kinetics. The flexibility of this measurement method was demonstrated in this paper. This method was first applied to study scaling effects in phase change devices and it was found that scaling not only lowers programming current requirement, but also increases the phase change speed of the device. This suggests that high density and high speed phase change memory devices through scaling are achievable. The same method was applied to study the physical model of phase change and the evidence suggests that phase change in these devices does not proceed solely by nucleation, supporting the hypothesis of filament formation during phase change. This transient method would be an important analysis technique of novel phase change devices and materials.