High Operating Temperature Reliability of Optimized Ge-Rich GST Wall PCM Devices

The reliability of optimized Ge-rich GST "Wall" Phase Change Memory (PCM) devices is investigated at high operating temperatures. Endurance of more than 10^7 cycles is ensured up to 175 °C. A cell thermal resistance 45% higher wrt standard GST devices is demonstrated, granting reduced cell to cell thermal crosstalk. Increased temperatures show to have a limited impact on the programming speed. Finally, specific programming sequences are proposed to reduce the drift of intermediate resistance states at high temperature.