Enhanced Thermal Efficiency in Phase-Change Memory Cell by Double GST Thermally Confined Structure

A novel phase-change memory cell with a double- confinement structure was proposed and fabricated in this work. By having an additional bottom Ge₂Sb₂Te₅ layer under the electrically confined active region, the heat loss can be effectively prevented. The temperature uniformity over the active region significantly improves and so does the thermal efficiency. Therefore, a low I_RESET of about 0.3 mA and a reset power can be achieved. For the SET performance, a pulsewidth as low as 200 ns can be used without compromising the R_SET.