Nanoscale Advanced Materials Engineering via Localised Ion Doping

通过局部离子掺杂进行纳米级先进材料工程

• 批准号: 2106105
• 金额: --
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Studentship
• 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=studentship-2106105
• 关键词: Nanoscale; Advanced; Materials; Engineering; via

Most advanced materials are actually composite systems where each part is specifically tailored to provide a particular functionality, often via doping. In electronic devices this may be p- or n-type behaviour (the preference to conduct positive of negative charges), in optical devices the ability to emit light at a given wavelength (such as in the infrared for optical fibre communications), or in magnetic materials the ability to store information based on the direction of a magnetic field for example. To enable the realisation of new devices it is essential to increase the density of functionality within a given device volume. Simple miniaturisation (i.e. to fit more devices of the same type but of smaller size) is limited in scope as the nanoscale regime is reached, not only by the well-known emergence of quantum effects, but by the simple capability to control the materials engineering on this scale. Self-assembly methods for example enable the creation of 0D (so called 'quantum dots' or 'artificial atoms'), 1D (wire-like) and 2D (sheet-like) materials with unique properties, but the subsequent control and modification of these is non-trivial and has yet to be demonstrated in many cases. This research project will support the establishment of a world-leading Platform for Nanoscale Advanced Materials Engineering (P-NAME) facility that incorporates a new tool which will provide the capability required to deliver a fundamental change in our ability to design and engineer materials. The specific objectives of the project are:- to develop and validate the P-NAME tool capability to deliver nanoscale doping of semiconductor materials;- to develop advanced doped materials processing methods in order to activate doped atoms and repair implantation damage;- to develop suitable characterization protocols to study the effect of nanoscale doping;- to demonstrate an exemplar photonic/spintronic device realized via nanoscale doping.These objectives are to be addressed using the recently commissioned P-NAME tool that will enable high resolution imaging, doping and patterning of materials with multiple ion species at low energies and high doses to locally engineer materials, giving a unique capability for advanced materials engineering providing nanoscale functionality on demand. Ion species including B, P, As and Sb (for Si), key transition metals (e.g. Ti, V, Mn, Co, Ni) and the rare-earth ions, and other technologically important species (e.g. Pd, Pt, Bi) will be provided using liquid-metal alloy ion sources. The tool will incorporate a mass filter to enable ion species (and isotope) separation and is designed using a modular LMAIS concept to enable efficient change over between sources.The ion dose and energy may be spatially varied to enable a wide parameter range to be accessed and studied. Ion doses will range from very low (e.g. ~10 ions) through to levels typically used to electronically dope semiconductors (1014 - 1016 ions/cm2) and higher. The ion energy range will be from 5 keV (to enable shallow doping in thin films) upwards to 40 keV. Higher energies are also available through the use of doubly charged ions etc. selected using the ExB mass filter. Dopant species may be varied and material synthesis performed in-situ on the nano-scale with an ion beam spot size of 20nm available for high-precision doping. This along with nanometer-precision sample handling and integrated ion beam control provide a IBL capability not previously available. This will enable localised ion doping of pre-deposited nanostructures and devices (e.g. nanowire pn-junctions, Si-photonics...), or of in-situ structures created using IBL.Validation will involve the doping of test samples and study using HRTEM, THz-spectroscopy and scanning probe spectroscopy as appropriate. This will be done in collaboration with others.

大多数先进材料实际上是复合体系，其中每个部分都是专门定制的，以提供特定的功能，通常是通过掺杂。在电子器件中，这可以是p型或n型行为(偏爱导电正电荷或负电荷)，在光学器件中，这可以是在给定波长发射光的能力(例如，在用于光纤通信的红外中)，或者在磁性材料中，这可以是基于磁场方向存储信息的能力。要实现新设备，必须增加给定设备卷内的功能密度。随着纳米尺度的到来，简单的小型化(即适应更多相同类型但尺寸更小的设备)的范围受到限制，不仅受到众所周知的量子效应的出现，而且受到在这种规模上控制材料工程的简单能力的限制。例如，自组装方法能够产生具有独特性质的0维(所谓的‘量子点’或‘人造原子’)、1维(线状)和2维(片状)材料，但随后对这些材料的控制和修饰不是微不足道的，并且在许多情况下还没有得到证明。该研究项目将支持建立一个世界领先的纳米级先进材料工程(P-NAME)设施平台，其中包括一种新工具，该工具将提供所需的能力，使我们的材料设计和工程能力发生根本性变化。该项目的具体目标是：-开发和验证P-NAME工具提供纳米级半导体材料掺杂的能力；-开发先进的掺杂材料处理方法，以激活掺杂原子并修复注入损伤；-开发适当的表征协议，研究纳米级掺杂的影响；-展示通过纳米级掺杂实现的示范光子/自旋电子器件。这些目标将使用最近投入使用的P-NAME工具来解决，该工具将使具有多种离子物种的材料在低能量和高剂量下进行高分辨率成像、掺杂和图案化，以本地工程材料，为先进材料工程提供按需提供纳米级功能的独特能力。包括B、P、As和Sb(对于Si)、关键过渡金属(例如，Ti、V、Mn、Co、Ni)和稀土离子以及其他具有重要技术价值的物种(例如，Pd、铂、铋)的离子物种将使用液态金属合金离子源提供。该工具将包括一个质量过滤器，以实现离子物种(和同位素)的分离，并使用模块化的LMAIS概念进行设计，以实现源之间的有效转换。离子剂量和能量可以在空间上变化，以便能够访问和研究广泛的参数范围。离子剂量将从非常低的(例如~10个离子)到通常用于电子掺杂半导体的水平(1014-1016ion/cm2)甚至更高。离子能量范围将从5keV(以实现薄膜的浅掺杂)到40keV。更高的能量也可以通过使用ExB质量过滤器选择的双电荷离子等来获得。掺杂种类可以改变，材料合成可以在纳米尺度上原位进行，离子束光斑尺寸为20 nm，可用于高精度掺杂。这与纳米精度的样品处理和集成的离子束控制一起提供了以前不可用的IBL能力。这将使预先沉积的纳米结构和设备(例如纳米线pn结、硅光子学...)或使用IBL创建的原位结构的局部离子掺杂成为可能。验证将涉及测试样品的掺杂，并视情况使用HRTEM、THz光谱和扫描探针光谱进行研究。这将与其他人合作完成。