Xiaoying Wan, Chengqi Zhang, Jiahui Li, Zhaofu Zhang, Qingbo Wang, Hai Wang, Jun Liu, Hong-Xia Zhong
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In contrast, no apparent chemical bonding and weak charge transfer are observed in the weak interaction interfaces formed with Au, Cu, and Ag. Additionally, our study reveals the presence of a pronounced Fermi level pinning effect between monolayer Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub>and metals, with pinning factors of<i>S<sub>n</sub></i>=0.325 and<i>S<sub>p</sub></i>=0.350. By increasing the interlayer distance, an effective transition from n-type Ohmic contact to n-type Schottky contact is facilitated because the band edge of Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub>is shifted upwards. Our study not only provides a theoretical basis for selecting suitable metal electrodes in Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub>-based devices but also holds significant implications for understanding Schottky barrier height modulation between semiconductors and metals.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":null,"pages":null},"PeriodicalIF":2.3000,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Exploring Charge Transfer and Schottky Barrier Modulation at Monolayer Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub>-Metal Interfaces.\",\"authors\":\"Xiaoying Wan, Chengqi Zhang, Jiahui Li, Zhaofu Zhang, Qingbo Wang, Hai Wang, Jun Liu, Hong-Xia Zhong\",\"doi\":\"10.1088/1361-648X/ad7804\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>Monolayer Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub>exhibits great potential in non-volatile memory technology due to its excellent electronic properties and phase-change characteristics, while the fundamental nature of Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub>-metal contacts has not been well understood yet. 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引用次数: 0
摘要
单层 Ge2Sb2Te5 因其优异的电子特性和相变特性而在非易失性存储器技术中展现出巨大的潜力,但人们对 Ge2Sb2Te5 与金属接触的基本性质还不甚了解。在此,我们基于第一性原理计算,对单层 Ge2Sb2Te5 与铂、钯、金、铜、铬、银和钨接触之间的电子特性进行了全面的 ab initio 研究。我们发现,单层 Ge2Sb2Te5 与 Pt、Pd、Cr 和 W 触点之间形成的强相互作用界面显示出化学键和强电荷转移。相反,在与金、铜和银形成的弱相互作用界面中,没有观察到明显的化学键和弱电荷转移。此外,我们的研究还揭示了单层 Ge2Sb2Te5 与金属之间存在明显的费米级针销效应,针销因子分别为 Sn=0.325 和 Sp=0.350。通过增加层间距离,促进了从 n 型欧姆接触到 n 型肖特基接触的有效过渡,因为 Ge2Sb2Te5 的带边缘向上移动了。我们的研究不仅为在基于 Ge2Sb2Te5 的器件中选择合适的金属电极提供了理论依据,而且对理解半导体与金属之间的肖特基势垒高度调制具有重要意义。
Exploring Charge Transfer and Schottky Barrier Modulation at Monolayer Ge2Sb2Te5-Metal Interfaces.
Monolayer Ge2Sb2Te5exhibits great potential in non-volatile memory technology due to its excellent electronic properties and phase-change characteristics, while the fundamental nature of Ge2Sb2Te5-metal contacts has not been well understood yet. Here, we provide a comprehensive ab initio study of the electronic properties between monolayer Ge2Sb2Te5and Pt, Pd, Au, Cu, Cr, Ag, and W contacts based on first-principles calculations. We find that the strong interaction interfaces formed between monolayer Ge2Sb2Te5and Pt, Pd, Cr, and W contacts show chemical bonding and strong charge transfer. In contrast, no apparent chemical bonding and weak charge transfer are observed in the weak interaction interfaces formed with Au, Cu, and Ag. Additionally, our study reveals the presence of a pronounced Fermi level pinning effect between monolayer Ge2Sb2Te5and metals, with pinning factors ofSn=0.325 andSp=0.350. By increasing the interlayer distance, an effective transition from n-type Ohmic contact to n-type Schottky contact is facilitated because the band edge of Ge2Sb2Te5is shifted upwards. Our study not only provides a theoretical basis for selecting suitable metal electrodes in Ge2Sb2Te5-based devices but also holds significant implications for understanding Schottky barrier height modulation between semiconductors and metals.
期刊介绍:
Journal of Physics: Condensed Matter covers the whole of condensed matter physics including soft condensed matter and nanostructures. Papers may report experimental, theoretical and simulation studies. Note that papers must contain fundamental condensed matter science: papers reporting methods of materials preparation or properties of materials without novel condensed matter content will not be accepted.