RESET Current Reduction for Phase Change Memory Based on Standard 0.13-μm CMOS Technology

In order to reduce the RESET current of phase change memory (PCM), which is fabricated using standard 0.13-μm CMOS technology, we have investigated various process factors that might affect the phase transition process, including doping concentration, diameter of bottom electrode contact (BEC) and different chalcogenide materials. Test results suggest that the PCM memory cell, utilizing Si2Sb2Te5 (SST) material as storage element with 80 nm BEC, can be operated using a 40 ns electrical pulse with current amplitude as small as 0.5 mA. This is mainly resulted from the high electrical resistances of the novel chalcogenide both in amorphous and crystalline state, which contribute greatly to the improved efficiency of heating process.