Analysis of Stuck Reset Failure in Phase-Change Memory by Calculating Phase-Change Stress using Finite Element Simulation

Abstract

Stuck reset is an open-circuit failure that occurs in phase-change memory (PCM) after repeated reset and set operations, that is, endurance cycling. Stuck reset is majorly caused by phase-change stress, which is the mechanical stress induced during a reset operation due to the density difference between the amorphous and crystalline phases of the phase-change material. This indicates that a reduction in phase-change stress may improve the endurance characteristics of PCM. Herein, a simulation technique for the calculation of phase-change stress using a finite-element software is proposed. Subsequently, a comparative study of the endurance of different PCM device architectures is performed. The results reveal that the self-heating architecture exhibits superior endurance compared to the heater-based architecture. Furthermore, the void locations in the experiments coincide with the most highly stressed locations in the simulation.