Cr-doped Ge{sub 2}Sb{sub 2}Te{sub 5} for ultra-long data retention phase change memory

Journal Article · Mon Nov 30 04:00:00 EST 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4936847· OSTI ID:22486154

Wang, Qing; Xia, Yangyang; Zheng, Yonghui; Zhang, Qi ^[1]; Liu, Bo; Song, Sannian; Cheng, Yan; Song, Zhitang; Feng, Songlin ^[1]; Huo, Ruru ^[1]

---

1. State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Micro-system and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China)

Phase change memory is regarded as one of the most promising candidates for the next-generation non-volatile memory. Its storage medium, phase change material, has attracted continuous exploration. Ge{sub 2}Sb{sub 2}Te{sub 5} (GST) is the most popular phase change material, but its thermal stability needs to be improved when used in some fields at high temperature (more than 120 °C). In this paper, we doped Cr atoms into GST and obtained Cr{sub 10}(Ge{sub 2}Sb{sub 2}Te{sub 5}){sub 90} (labeled as Cr-GST) with high thermal stability. For Cr-GST film, the sheet resistance ratio between amorphous and crystalline states is high up to 3 orders of magnitude. The crystalline Cr-GST film inherits the phase structure of GST, with metastable face-centered cubic phase and/or stable hexagonal phase. The doped Cr atoms not only bond with other atoms but also help to improve the anti-oxidation property of Cr-GST. As for the amorphous thermal stability, the calculated temperature for 10-year-data-retention of Cr-GST film, based on the Arrhenius equation, is about 180 °C. The threshold current and threshold voltage of a cell based on Cr-GST are about 6 μA and 2.7 V. The cell could be operated by suitable voltages for more than 40 000 cycles. Thus, Cr-GST is proved to be a promising phase change material with ultra-long data retention.

• OSTI ID: 22486154
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 22 Vol. 107; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ARRHENIUS EQUATION
CRYSTALS
DOPED MATERIALS
ELECTRIC POTENTIAL
FCC LATTICES
FILMS
OXIDATION
PHASE CHANGE MATERIALS
STABILITY
TEMPERATURE RANGE 0400-1000 K
THRESHOLD CURRENT