Non-Arrhenius pulse-induced crystallization in phase change memories

Crystallization kinetics in phase change memory (PCM) control the device switching and retention times, thus an accurate characterization and prediction of crystallization speed is essential. We measured crystallization times in PCM devices in both the thermal crystallization regime at relatively low temperature (T <; 250 °C) and in pulsed-induced crystallization (set regime). By using a filamentary model for set transition, we evidence a non-Arrhenius temperature dependence of crystallization. This finding provides a key new element for the modeling of phase change materials and devices.