Compact Thermal Model for Vertical Nanowire Phase-Change Memory Cells

We introduce a compact model for the temperature distribution in cylindrical nanowire (NW) phase-change memory (PCM) cells for both transient (nanoseconds) and steady-state time scales. The model takes advantage of the symmetry of the cell to efficiently calculate temperature distribution dependence on geometry and material/interface properties. The results are compared with data from the literature and with finite-element simulations, showing improved computation speed by two orders of magnitude. Programming current sensitivity to cell dimensions and material properties is investigated, indicating that NW diameter (D) and thermal boundary resistance (TBR) play the strongest role in enhancing PCM energy efficiency.

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