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http://dx.doi.org/10.4313/JKEM.2022.35.1.7

A Study on the Electrical Characteristics of Ge2Sb2Te5/Ti/W-Ge8Sb2Te11 Structure for Multi-Level Phase Change Memory  

Oh, Woo-Young (Department of Advanced Chemicals and Engineering, Chonnam National University)
Lee, Hyun-Yong (School of Chemical Engineering, Chonnam National University)
Publication Information
Journal of the Korean Institute of Electrical and Electronic Material Engineers / v.35, no.1, 2022 , pp. 44-49 More about this Journal
Abstract
In this paper, we investigated current (I)- and voltage (V)-sweeping properties in a double-stack structure, Ge2Sb2Te5/Ti/W-doped Ge8Sb2Te11, a candidate medium for applications to multilevel phase-change memory. 200-nm-thick and W-doped Ge2Sb2Te5 and W-doped Ge8Sb2Te11 films were deposited on p-type Si(100) substrate using magnetron sputtering system, and the sheet resistance was measured using 4 point-probe method. The sheet resistance of amorphous-phase W-doped Ge8Sb2Te11 film was about 1 order larger than that of Ge2Sb2Te5 film. The I- and V-sweeping properties were measured using sourcemeter, pulse generator, and digital multimeter. The speed of amorphous-to-multilevel crystallization was evaluated from a graph of resistance vs. pulse duration (t) at a fixed applied voltage (12 V). All the double-stack cells exhibited a two-step phase change process with the multilevel memory states of high-middle-low resistance (HR-MR-LR). In particular, the stable MR state is required to guarantee the reliability of the multilevel phase-change memory. For the Ge2Sb2Te5 (150 nm)/Ti (20 nm)/W-Ge8Sb2Te11 (50 nm), the phase transformations of HR→MR and MR→LR were observed at t<30ns and t<65ns, respectively. We believe that a high speed and stable multilevel phase-change memory can be optimized by the double-stack structure of proper Ge-Sb-Te films separated by a barrier metal (Ti).
Keywords
Multilevel phase change memory; Double-stack structure; $Ge_2Sb_2Te_5$; W-doped $Ge_8Sb_2Te_{11}$; Sputtering;
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1 R. Liu, A. Hu, Z. Zhao, H. Zhou, J. Zhai, X. Zhou, S. Song, and Z. Song, Scripta Mater., 178, 324 (2020). [DOI: https://doi.org/10.1016/j.scriptamat.2019.11.054]   DOI
2 Y. Ren, R. Sun, S.H.Y. Chen, C. Du, S. T. Han, and Y. Zhou, Phys. Status Solidi RRL, 15, 2000394 (2021). [DOI: https://doi.org/10.1002/pssr.202000394]   DOI
3 K. H. Song, S. W. Kim, J. H. Seo, and H. Y. Lee, J. Appl. Phys., 104, 103516 (2008). [DOI: https://doi.org/10.1063/1.3026720]   DOI
4 S. W. Kim, K. H. Song, and H. Y. Lee, J. Korean Inst. Electr. Electron. Mater. Eng., 21, 629 (2008). [DOI: https://doi.org/10.4313/JKEM.2008.21.7.629]   DOI
5 S. R. Ovshinsky, Phys. Rev. Lett., 21, 1450 (1968). [DOI: https://doi.org/10.1103/PhysRevLett.21.1450]   DOI
6 C. J. Park, J. B. Yeo, H. Kong, and H. Y. Lee, J. Korean Inst. Electr. Electron. Mater. Eng., 30, 133 (2017). [DOI: https://doi.org/10.4313/jkem.2017.30.3.133]   DOI
7 L. Zheng, W. Song, Z. Song, and S. Song, ACS Appl. Mater. Interfaces, 11, 45885 (2019). [DOI: https://doi.org/10.1021/acsami.9b16876]   DOI
8 Z. He, W. Wu, X. Liu, J. Zhai, T. Lai, S. Song, and Z. Song, Mater. Lett., 185, 399 (2016). [DOI: https://doi.org/10.1016/j.matlet.2016.09.021]   DOI
9 K. Jiang, Y. Lu, Z. Li, M. Wang, X. Shen, G. Wang, S. Song, and Z. Song, Mater. Sci. Eng. B, 231, 81 (2018). [DOI: https://doi.org/10.1016/j.mseb.2018.10.002]   DOI
10 K. Ding, K. Ren, F. Rao, Z. Song, L. Wu, B. Liu, and S. Feng, Mater. Lett., 125, 143 (2014). [DOI: https://doi.org/10.1016/j.matlet.2014. 03.180]   DOI
11 I. Friedrich, V. Weidenhof, W. Njoroge, P. Franz, and M. Wuttig, J. Appl. Phys., 87, 4130 (2000). [DOI: https://doi.org/10.1063/1.373041]   DOI
12 N. Yamada, E. Ohno, K. Nishiuchi, N. Akahira, and M. Takao, J. Appl. Phys., 69, 2849 (1991). [DOI: https://doi.org/10.1063/1.348620]   DOI
13 K. H. Song, S. C. Baek, and H. Y. Lee, J. Korean Phys. Soc., 61, 10 (2012). [DOI: https://doi.org/10.3938/jkps.61.10]   DOI
14 L. Waldecker, T. A. Miller, M. Rude, R. Bertoni, J. Osmond, V. Pruneri, R. E. Simpson, R. Ernstorfer, and S. Wall, Nat. Mater., 14, 991 (2015). [DOI: https://doi.org/10.1038/nmat4359]   DOI
15 J. H. Park, S. W. Kim, J. H. Kim, Z. Wu, S. L. Cho, D. Ahn, D. H. Ahn, J. M. Lee, S. U. Nam, and D. H. Ko, J. Appl. Phys., 117, 115703 (2015). [DOI: https://doi.org/10.1063/1.4914909]   DOI
16 S. Tyson, G. Wicker, T. Lowrey, S. Hudgens, and K. Hunt, Proc. 2000 IEEE Aerospace Conference. Proceedings (Cat. No. 00TH8484) (IEEE, Big Sky, USA, 2000) p. 385. [DOI: https://doi.org/10.1109/aero.2000.878512]   DOI
17 P. Guo, A. M. Sarangan, and I. Agha, Appl. Sci., 9, 530 (2019). [DOI: https://doi.org/10.3390/app9030530]   DOI