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Atomic migration on Phase Change Memory devices with wall architecture has been experimentally investigated and a quantitative model including electrical, thermal, and mechanical driving forces has been developed. The experimental results collected by driving the device with programming pulses with direct and reverse polarity have been accounted for. Comparison with data of atomic migration on heavily cycled cells is also provided

Discontinuity of electrical and thermal conductivity values at melt has been reported in phase change materials. Signatures of the effect are found in phase change memory cells with Wall architecture. A quantitative model describing the dependence on temperature of electrical and thermal conductivity values of the phase change alloy is introduced, covering the range from solid phase to beyond melt. The model has been implemented in a 3-D electro-thermal TCAD tool and successfully validated against the experimental results

Cycling-induced threshold-voltage instabilities in NAND Flash memory arrays are investigated via compact modeling of the NAND string. Calibration against experimental data allows the extraction of the model parameters and of their dependence on cycling dose and post-cycling bake time. Results are used to study the impact of charge trapping/detrapping in the tunnel oxide and interface state generation/annealing on the damage creation and recovery dynamics. It is shown that the former mechanism represents the main responsible for thresholdvoltage instabilities, while interface states come into play at high read currents, accelerating the threshold-voltage transients and lowering their activation energy during bakes below 1.1 eV.