Writing nanomagnets: Investigation of new magnetic nanostructures fabricated by focussed electron and ion beams

写入纳米磁体：研究通过聚焦电子和离子束制造的新型磁性纳米结构

• 批准号: EP/M008517/2
• 负责人: Amalio Fernandez-Pacheco
• 金额: $ 24.18万
• 依托单位: University of Glasgow
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FM008517%2F2
• 关键词: Writing; nanomagnets; Investigation; new; magnetic

The objective of this fellowship is the investigation of new nanomagnetic materials fabricated by focussed electron and ion beam deposition (FEBID/FIBID), which has a huge technological interest for spintronic applications. Nanomagnets are magnetic systems with nanometric dimensions, i.e. they are formed just by a few atoms along their length, width and/or thickness. Because their dimensions become of the order of the fundamental lengths governing their properties, they behave differently from macroscopic magnets, which has made possible their exploitation in many applications. In particular, the development of new types of nanomagnets is one of the key ingredients for the vast increase in computer performance during the last decades, since both storage and sensing part of hard disk drives are formed by this type of nanostructures. In order to continue the exponential increase in computing performance, new technologies should involve greater miniaturisation, higher speeds and lower power consumption. Spintronics is the area of electronics which exploits new physical phenomena in nanomagnets to store and process information, and some spintronic devices such as STT-MRAMs or racetrack memories have been proposed as promising alternatives to CMOS technology. However, it is clear that in order to have a revolutionary impact in computing, spintronics needs of new ways to fabricate magnetic nanostructures. Standard processes used now to pattern magnetic systems at the nanoscale are based on thin film deposition using physical methods and lithography techniques using masks and resists; these top-down methods are facing their physical limits and RAM and CPU operations are fully dominated by transistor technology. It is therefore urgently needed to study more advanced fabrication techniques which use bottom-up approaches, where molecules serve as building blocks for the fabrication of functional nanomaterials.The techniques to be used in this project, (FEBID/FIBID) are direct-writing nanolithography techniques based on the local chemical vapour deposition of gas molecules adsorbed on a substrate as a result of the interaction with high energy focussed beams of electrons or ions (SEM or FIB). These ultra-high resolution rapid processing techniques are extremely flexible, not needing either masks or resists. Specifically, they have a unique capability to fabricate complex three-dimensional nanostructures on any surface. The main drawback usually found when using these processes is that due to the poor decomposition efficiency of the molecules under focussed beams, the material deposited is a mixture of elements coming from the precursor gas molecules, having properties far from those pursued. Magnetic materials are however the exception to this negative scenario, since under the appropriate growth conditions and using carbonyls of 3d-ferromagnetic metals, pure magnetic materials can be directly deposited. Due to the recent birth of these techniques, previous results using FEBID/FIBID of magnetic materials have been mostly devoted to study the purity of the deposits and to reproduce results previously obtained by standard patterning techniques. This project will go several steps further exploiting the unique capabilities of FE/IBID for the fabrication of magnetic nanostructures. By varying the deposition conditions, a new set of nanomagnetic materials will be studied, where the microstructure and composition will be controlled at the nanoscale. By combining gas precursors and focussed beams, different types of magnetic compounds will be fabricated, as well as multi-layered nanostructures. Moreover, the growth of complex three-dimensional nanomagnets will permit to create the first devices which can store and process magnetic information in all three directions. In order to characterise these systems, a combination of magnetic, structural and spectroscopy techniques together with magnetic imaging and simulations will be used.

该奖学金的目的是研究通过聚焦电子和离子束沉积（FEBID/FIBID）制造的新型纳米磁性材料，这对自旋电子应用具有巨大的技术兴趣。纳米磁体是具有纳米尺寸的磁性系统，即它们仅由沿其长度、宽度和/或厚度的几个原子形成。由于它们的尺寸达到了控制其特性的基本长度的量级，因此它们的行为与宏观磁体不同，这使得它们在许多应用中得到利用成为可能。特别是，新型纳米磁体的开发是过去几十年计算机性能大幅提高的关键因素之一，因为硬盘驱动器的存储和传感部分都是由这种类型的纳米结构形成的。为了继续使计算性能呈指数级增长，新技术应涉及更大的小型化、更高的速度和更低的功耗。自旋电子学是利用纳米磁体中的新物理现象来存储和处理信息的电子领域，并且一些自旋电子器件（例如 STT-MRAM 或赛道存储器）已被提议作为 CMOS 技术的有前途的替代品。然而，很明显，为了对计算产生革命性影响，自旋电子学需要新的方法来制造磁性纳米结构。现在用于纳米级磁系统图案化的标准工艺基于使用物理方法的薄膜沉积以及使用掩模和抗蚀剂的光刻技术；这些自上而下的方法面临着物理限制，RAM 和 CPU 操作完全由晶体管技术主导。因此，迫切需要研究使用自下而上方法的更先进的制造技术，其中分子作为功能纳米材料制造的构建块。该项目中使用的技术（FEBID/FIBID）是直写纳米光刻技术，基于由于与高能聚焦相互作用而吸附在基板上的气体分子的局部化学气相沉积。 电子或离子束（SEM 或 FIB）。这些超高分辨率快速处理技术非常灵活，不需要掩模或抗蚀剂。具体来说，他们具有在任何表面上制造复杂的三维纳米结构的独特能力。使用这些工艺时通常发现的主要缺点是，由于聚焦光束下分子的分解效率较差，沉积的材料是来自前体气体分子的元素的混合物，其性能与所追求的性能相去甚远。然而，磁性材料是这种负面情况的例外，因为在适当的生长条件下并使用 3d 铁磁金属的羰基，可以直接沉积纯磁性材料。由于这些技术最近诞生，以前使用磁性材料的 FEBID/FIBID 的结果主要致力于研究沉积物的纯度并重现以前通过标准图案化技术获得的结果。该项目将进一步利用 FE/IBID 的独特功能来制造磁性纳米结构。通过改变沉积条件，将研究一组新的纳米磁性材料，其微观结构和成分将在纳米尺度上进行控制。通过结合气体前驱体和聚焦光束，将制造出不同类型的磁性化合物以及多层纳米结构。此外，复杂三维纳米磁体的生长将允许创建第一个可以在所有三个方向上存储和处理磁信息的设备。为了表征这些系统，将结合使用磁性、结构和光谱技术以及磁性成像和模拟。

项目成果

High-Fidelity 3D-Nanoprinting via Focused Electron Beams: Computer-Aided Design (3BID)

• DOI: 10.1021/acsanm.7b00342
• 发表时间: 2018-03-01
• 期刊: ACS APPLIED NANO MATERIALS
• 影响因子: 5.9
• 作者: Fowlkes, Jason D.;Winkler, R.;Plank, H.
• 通讯作者: Plank, H.

Non-Planar Geometrical Effects on the Magnetoelectrical Signal in a Three-Dimensional Nanomagnetic Circuit.

• DOI: 10.1021/acsnano.0c10272
• 发表时间: 2021-04-27
• 期刊: ACS nano
• 影响因子: 17.1
• 作者: Meng F;Donnelly C;Abert C;Skoric L;Holmes S;Xiao Z;Liao JW;Newton PJ;Barnes CHW;Sanz-Hernández D;Hierro-Rodriguez A;Suess D;Cowburn RP;Fernández-Pacheco A
• 通讯作者: Fernández-Pacheco A

Fabrication of Scaffold-Based 3D Magnetic Nanowires for Domain Wall Applications.

• DOI: 10.3390/nano8070483
• 发表时间: 2018-06-30
• 期刊: Nanomaterials (Basel, Switzerland)
• 作者: Sanz-Hernández D;Hamans RF;Osterrieth J;Liao JW;Skoric L;Fowlkes JD;Rack PD;Lippert A;Lee SF;Lavrijsen R;Fernández-Pacheco A
• 通讯作者: Fernández-Pacheco A

Micromagnetic modeling of magnetic domain walls in curved cylindrical nanotubes and nanowires

• DOI: 10.1063/5.0050872
• 发表时间: 2021-03
• 期刊: Applied Physics Letters
• 影响因子: 4
• 作者: L. Skoric;Claire Donnelly;C. Abert;Aurelio Hierro-Rodriguez;Dieter Suess;A. Fernández-Pacheco

Complex free-space magnetic field textures induced by three-dimensional magnetic nanostructures.

• DOI: 10.1038/s41565-021-01027-7
• 发表时间: 2022-03
• 期刊: Nature nanotechnology
• 影响因子: 38.3
• 作者: Donnelly C;Hierro-Rodríguez A;Abert C;Witte K;Skoric L;Sanz-Hernández D;Finizio S;Meng F;McVitie S;Raabe J;Suess D;Cowburn R;Fernández-Pacheco A
• 通讯作者: Fernández-Pacheco A