Resistance Drift Suppression Utilizing GeTe/Sb2Te3 Superlattice‐Like Phase‐Change Materials

Abstract Resistance drift is one of the key challenges in phase‐change memory, especially in multilevel storage applications. Although many efforts have been proposed to reduce the probability error caused by resistance drift, the most effective method to suppress resistance drift is by material design. Since resistance drift in amorphous materials comes from changes in the distributions of defects and tail states that are caused by spontaneous structural relaxation, it is possible to suppress resistance drift by confine defect relaxation. A superlattice‐like structure is used to construct relatively controllable interfaces different from those inherent in amorphous chalcogenide for the regulation of resistance drift. By adjusting structural parameters, amorphous GeTe/Sb 2 Te 3 achieves a very low resistance drift. A low‐field electrical transport test based on a trapping band model shows that a change in the structural parameters directly affects the transport process in GeTe/Sb 2 Te 3 such that the resistance drift is suppressed. X‐ray photoelectron spectroscopy characterization reveals that defects at interfaces in superlattice‐like GeTe/Sb 2 Te 3 vary with the structural parameters. Compared with traditional doping and other methods, the interfacial structure introduces controllable defects and provides another strategy for the design of multilevel data storage.