Electrothermal and phase-change dynamics in chalcogenide-based memories
ABSTRACT We analyzed the programming dynamics in phase-change memory (PCM) cells. The chalcogenide phase-change mechanism and phase distribution in the programmed cell is studied by both experiments and a numerical model, which self-consistently addresses the electrical-thermal conduction phase transition. We show that the reset-set transition is strongly coupled to the electronic switching in the amorphous phase, thus supporting the need for a self-consistent electrothermal-phase transition model to correctly account for all experimental evidences.
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ABSTRACT: A key issue in nonvolatile storage is long-term data retention. This aspect is even more important in innovative storage technologies such as phase-change memory (PCM), which promises better performance and easier scalability with respect to traditional Flash memory and potential for multilevel storage. In this respect, we experimentally investigated the stability of intermediate states obtained by means of partial-SET programming. To this end, we analyzed the effects of the width and the amplitude of the programming pulses on the degradation of intermediate programmed resistance levels over time in PCM cells. Our study was carried out by considering the average behavior of an array of PCM cells, showing that data-retention properties degrade as the programming thermal stress increases.IEEE Transactions on Electron Devices 03/2011; · 2.32 Impact Factor