Development of quasi-2D Si devices with large magnetoresistance

大磁阻准二维硅器件的研制

• 批准号: 21K04822
• 负责人: Aurelie Spiesser
• 金额: $ 2.75万
• 依托单位: National Institute of Advanced Industrial Science and Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2021
• 资助国家: 日本
• 起止时间: 2021-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-21K04822/
• 关键词: silicon spintronics; magnetic tunnel contact; spin transport; thin channel; novel tunnel barrier; Si spintronics; Spin transport; Magnetic tunnel contacts; Thin channel; magnetic tunnel contacts; magnetoresistance; 2-dimensional channel

1) Spin transport in thin Si channels:We have deposited Fe/MgO on thin silicon channels having thicknesses ranging from 70 nm to 25 nm. We used molecular beam epitaxy to grow Fe/MgO, and the RHEED patterns indicate high quality epitaxial Fe/MgO. We then fabricated devices and measured spin transport properties as a function of the Si channel thickness. We observed clear two-terminal magnetoresistance (2T-MR) for all the devices. Although an increase of the 2T-MR was observed as the Si channel thickness decreases, the resistivity of the Si channel increased with decreasing the channel thickness. This prevented us from interpreting the results in a systematic manner, as one need to keep the resistivity constant in order to compare the results.2) Novel tunnel barrier for spin injection into Si:We investigated the epitaxial growth of BaO on Si as a novel tunnel barrier. The BaO lattice matches that of Si better than MgO. Therefore, higher quality epitaxial BaO might be obtained on Si, and potentially be a better fit as a tunnel barrier for Si spin transport devices. We investigated different growth temperature for BaO and found the optimum growth conditions to obtain epitaxial BaO on Si.3) Optimum contact resistance for 2T-MR in Si-based spin transport devicesThe 2T-MR in spin transport devices was determined for devices with a Si channel and Fe/MgO tunnel contacts of varying MgO thickness. We showed that the optimum and scaling of the 2T-MR are profoundly affected by the variation of the spin polarization with contact resistance. The results were published in APL (2023).

1）在薄的Si通道中自旋转运：我们在厚度为70 nm至25 nm的厚度硅通道上沉积了Fe/Mgo。我们使用分子束外延来生长Fe/Mgo，而Rheed模式表示高质量的外延Fe/Mgo。然后，我们制造的设备并测量了自旋传输特性，这是SI通道厚度的函数。我们观察到所有设备的清晰的两端磁阻（2T-MR）。尽管随着SI通道厚度的降低，观察到2T-MR的增加，但随着通道厚度的减小，SI通道的电阻率增加。这阻止了我们以系统的方式解释结果，因为需要保持电阻率恒定以比较结果。2）2）新型的隧道屏障将自旋注射到SI中：我们研究了BAO在SI上的外延生长作为新型的隧道屏障。 BAO晶格比MGO更好地匹配SI的晶格。因此，可以在SI上获得更高质量的外延BAO，并且有可能成为SI自旋传输设备的隧道屏障。我们研究了BAO的不同生长温度，并发现在SI.3）基于SI通道和Fe/Mgo Mgo Mgo厚度的SI通道和Fe/Mgo隧道接触的设备中确定了SI基于SI的自旋传输Devicesthe 2T-MR的最佳生长条件。我们表明，2T-MR的最佳和缩放受到与接触电阻的自旋极化变化的深刻影响。结果发表在APL（2023）中。

项目成果

Superimposed contributions to two-terminal and nonlocal spin signals in lateral spin-transport devices

对横向自旋输运器件中两端和非局域自旋信号的叠加贡献

• DOI: 10.1103/physrevb.104.144419
• 发表时间: 2021
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Jansen R.;Spiesser A.;Fujita Y.;Saito H.;Yamada S.;Hamaya K.;Yuasa S.
• 通讯作者: Yuasa S.

Optimum contact resistance for two-terminal magnetoresistance in a lateral spin valve

横向自旋阀两端磁阻的最佳接触电阻

• DOI: 10.1063/5.0137482
• 发表时间: 2023
• 期刊: Applied Physics Letters
• 影响因子: 4
• 作者: A. Spiesser;R. Jansen;H. Saito;and S. Yuasa
• 通讯作者: and S. Yuasa