The importance of contacts in Cu2GeTe3 phase change memory devices
| Autor: | Keisuke Kobayashi, Yi Shuang, Yuta Saito, Alexander V. Kolobov, Satoshi Shindo, Shogo Hatayama, Yuji Sutou, Paul Fons |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
010302 applied physics
Materials science business.industry Schottky barrier General Physics and Astronomy Schottky diode 02 engineering and technology 021001 nanoscience & nanotechnology Thermal conduction 01 natural sciences Phase-change material Amorphous solid Phase-change memory X-ray photoelectron spectroscopy 0103 physical sciences Electrode Optoelectronics 0210 nano-technology business |
| Zdroj: | Journal of Applied Physics. 128:165105 |
| ISSN: | 1089-7550 0021-8979 |
| DOI: | 10.1063/5.0019269 |
| Popis: | Cu2GeTe3 (CGT) is a promising phase change material for phase change random access memory (PCRAM) applications because of its high thermal stability in the amorphous phase and its capability to undergo rapid phase change. In this paper, the electrical conduction mechanism of a CGT memory device fabricated using W electrodes (W/CGT) was investigated using current–voltage (I–V) measurements and angle resolved hard x-ray photoelectron spectroscopy (AR-HAXPES). The I–V characteristics of the W/CGT memory device were found to display non-linear behavior in the RESET (amorphous) state, while linear behavior was observed in the SET (crystalline) state, indicating that the W/CGT memory device exhibited Schottky conduction in the RESET state, but Ohmic conduction in the SET state. The effective Schottky barrier height was found to increase linearly as the ideality factor decreased to unity with the ideal W/CGT Schottky barrier height in the RESET state estimated to be 0.33 eV, a value in good agreement with the directly measured Schottky barrier height of 0.35 eV between W and amorphous CGT by AR-HAXPES measurements. These results suggest that the interface between the metal electrode and the phase change material plays an important role in PCRAM devices, and its comprehensive understanding is necessary for future application development. |
| Databáze: | OpenAIRE |
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