A chalcogenide material and memory device exhibiting fast operation over an extended range of reset state resistances. Electrical devices containing the chalcogenide materials permit rapid transformations from the reset state to the set state for reset and set states having a high resistance ratio. The devices provide for high resistance contrast of memory states while preserving fast operational speeds. The chalcogenide materials include Ge, Sb and Te where the Ge and/or Te content is lean relative to Ge.sub.2Sb.sub.2Te.sub.5. In one embodiment, the concentration of Ge is between 11% and 22%, the concentration of Sb is between 22% and 65%, and the concentration of Te is between 28% and 55%. In a preferred embodiment, the concentration of Ge is between 15% and 18%, the concentration of Sb is between 32% and 35%, and the concentration of Te is between 48% and 51%.
RELATED APPLICATION INFORMATION
This application is a continuation in part of U.S. patent application Ser. No. 11/200,466, entitled "Chalcogenide Devices Incorporating Chalcogenide Materials having Reduced Germanium or Tellurium Content", filed on Aug. 9, 2005; the disclosure of which is hereby incorporated by reference herein.