Temperature acceleration of structural relaxation in amorphous Ge2Sb2Te5

The structural relaxation (SR) process in an amorphous chalcogenide material (Ge2Sb2Te5) is studied by electrical measurements on phase-change memory devices. SR induces a change in the conduction regime from Poole to Poole–Frenkel transport, evidencing a temperature accelerated defect-annihilation process. Based on an Arrhenius kinetics with distributed activation energies, a temperature-acceleration law is shown, relating the time to reach a specific relaxed state to the temperature during isothermal experiments. This law is demonstrated comparing the time evolution of resistance for different temperatures. These results allow for a significant time reduction in reliability testing of devices and materials affected by SR.

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