Design And Simulation Of A High Performance Phase Change Memory Cell Based On Ga-SbTe

Phase change memory (PCM) becomes very hot in Non volatile memory (NVM) under 45nm process due to its special storage mode. PCM is expected as one of commercial mainstream NVM device in future and will take a very important role in memory market. However, several bottle nets like power, thermal stability and cycling ability restrict the development of PCM.In this paper, a novel phase change material was proposed, and a new prototype of Ga3Sb8Te1 based PCM device which has the lower power, high thermal stability and faster reset/set frequency. And then the performance of Ga3Sb8Te1 based PCM was investigated through the simulation model.The result of Finite Element Thermal Analysis, crystalline kinetics simulation and circuit model simulation are:1. Because of more TX/Tm ratio of Ga3Sb8Te1 based PCM, the thermal stress caused by phase change process when set and reset could be lowered down, which can enhance the cycling ability of the device; The reset current and power will shrink down along as device scaling down.2. The reset current of Ga3Sb8Te1 based PCM is about 1mA while Ge2Sb2Te5 based PCM is above 1.5mA when the feature size is 90nm; When feature size is 65nm, the current shrinks down to 0.6mA for Ga3Sb8Te1 based PCM and about 1mA for Ge2Sb2Te5 based PCM; In 45nm process, the reset current of Ga3Sb8Te1 based PCM is lower than 0.5mA. Thus Ga3Sb8Te1 based PCM shows the lower power than the universal GST based PCM.3. The reset and set frequency of Ga3Sb8Te1 based PCM is 100MHz and14MHz, the set frequency raised by 14.3% that compared to the universal GST Ge2Sb2Te5 based PCM; And the resistance ratio of amorphous and polycrystalline state is 500, so the logic stability is very high.4. Ga3Sb8Te1 based PCM can satisfy the optimum power transfer and has the scaling down ability.