Abstract
We investigated superlattice phase change memories (PCMs) to clarify which regions were responsible for switching. We observed atomic structures in a superlattice PCM film with a stack of GeTe / Sb2Te3 layers using atomically resolved EDX maps, and we found an intermixed region with three atom species of the Ge, Sb and Te around the top GeTe layer under the top electrode. We also found that a device with a GeTe layer on an Sb2Te3 layer without superlattice structure had the same switching characteristics as a device with a superlattice PCM, that had the same top GeTe layer. We developed and fabricated a modified superlattice PCM that attained ultra low Reset / Set currents under 60 μA.
Highlights
Phase change memories (PCMs) based on Ge, Sb and Te (GeSbTe) are promising candidates for replacing flash memories as next-generation solid-state memories
Some studies have been concluded on the atomic structures of superlattice PCMs using high angle annular dark field scanning transmission microscopy (HAADF-STEM)[7] and X-ray diffraction (XRD).[8]
A comparison of the switching characteristics in these different superlattice PCM structures revealed that the region around the top layer of the superlattice was responsible for the switching
Summary
Phase change memories (PCMs) based on Ge, Sb and Te (GeSbTe) are promising candidates for replacing flash memories as next-generation solid-state memories. A comparison of the switching characteristics in these different superlattice PCM structures revealed that the region around the top layer of the superlattice was responsible for the switching.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
