Innovative GeS2/Sb2Te3 based phase change memory for low power applications

In this paper, we analyze the electrical performance of a novel Phase-Change Memory (PCM) device based on GeS2/Sb2Te3 composition (GSST). Through physico-chemical analysis and electrical characterization we demonstrate a great reduction of the RESET programming current in unitary GSST devices. We show, how both electrical and thermal confinement improvement is achieved in GSST layers, contributing to the power efficiency increase of the device. Finally, an enhanced thermal stability of more than 290 °C is achieved. By TEM analysis of the fully integrated device we could demonstrate the phase separation between GeS2 and Sb2Te3, supporting the hypothesis that the device switches only in a reduced crystalline volume in a fully amorphous matrix. This result enables GSST PCM as a possible candidate for low power/high density memory applications.

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