Reliability analysis in GeTe and GeSbTe based phase-change memory 4 kb arrays targeting storage class memory applications

In this work, we propose a reliability analysis targeting the evaluation of the suitability of a Phase-Change Memory (PCM) device for Storage Class Memory (SCM) applications. Thanks to the analysis of programming and endurance characteristics in single devices and 4 kb arrays we compare two different GeTe and GeSbTe (αGST) based PCM. The evolution of the phase-change material along cycling is explained by the analysis of subthreshold characteristics and analytical equations based on experimental data for the description of electrical parameters evolution are given. An extrapolation method to evaluate endurance at more than 109 cycles required for SCM is described and applied, showing the intrinsic high endurance capability and suitability for SCM applications of αGST wrt GeTe.