Optimizing AsSeGe Chalcogenides by Dopants for Extremely Low IOFF, High Endurance and Low Vth Drift 3D Crosspoint Memory

Abstract

The doping effect on AsSeGe OTS materials is comprehensively studied. While B, C, S doped selectors suffer a stringent trade-off among Vth, IOFF and cycling endurance, Si and In doped selectors demonstrate an extremely low VtS (system threshold voltage when PCM is in SET state) and VtR (system threshold voltage when PCM is in RESET state) drift characteristics. We demonstrated true crosspoint operation (by half-V scheme) in a 1k by 1k cross-point ADM memory arrays from an In doped AsSeGe selector integrated with PCM with extremely low IOFF (~3nA from a total 100 crosspoint cells), wide VtS/VtR memory window (~2V main distribution memory window), 1E6 write cycles and low VtS and VtR drift characteristic (project<0.3V and 0.5V, respectively for one year) which is suggested for 3D crosspoint memory technology.