Title :
Multilevel Storage in Lateral Top-Heater Phase-Change Memory
Author :
Yin, You ; Ota, Kazuhiro ; Higano, Naoya ; Sone, Hayato ; Hosaka, Sumio
Author_Institution :
Dept. of Production Sci. & Technol., Gunma Univ., Kiryu
Abstract :
A lateral top-heater phase-change memory (LTH-PCM) is proposed and investigated for multilevel storage (MLS). The active layers are composed of a 50-nm-thick TiN layer as a top heater and a 150-nm-thick SbTeN layer. A number of intermediate levels, which are induced by electric currents, are exhibited in experimental results. They are distinct and very stable. The reversible switching of multilevels is successfully demonstrated in the LTH-PCM device. The MLS results from the gradual enlargement of crystalline region between electrodes by Joule heating according to our analysis.
Keywords :
antimony compounds; digital storage; phase changing circuits; tellurium compounds; titanium compounds; Joule heating; LTH-PCM device; SbTeN; TiN; crystalline region; electrodes; intermediate levels; lateral top-heater phase-change memory; multilevel storage; size 150 nm; size 50 nm; Argon; Conductivity; Crystallization; Multilevel systems; Phase change materials; Phase change memory; Semiconductor films; Sputtering; Tin; Voltage; Lateral; multilevel storage (MLS); nonvolatile memories; phase-change memories (PCMs); top heater;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2008.2000793
