Ion implantation into semiconductors: studying a new manufacturing technique

该项目将使用原子探针断层扫描（APT）研究离子注入半导体，并采用基于离子液体束的新型制造和表征技术。离子液体是阳离子和阴离子的混合物，没有中间溶剂。离子液体离子源（ILIS）是一种将液体覆盖在磨尖的针头上的装置。针受到电场的作用产生离子束。产生的光束可以用来处理材料。ILIS提供了多种离子化学物质，包括有机分子、简单原子卤素和高氟化物质。由于光束[1]中氟化物质的反应性，ILIS辐照后硅的快速蚀刻已被证明。ILIS可用于制造（例如微电子制造）和材料的高级表征。ILIS光束可以被聚焦并用于纳米级的材料研磨，从而实现断层扫描或制备透射电子显微镜的样品。ILIS也可用于二次离子质谱分析。该项目将研究ILIS离子注入半导体，如果ILIS用于制造或表征，应该了解这一点。APT可以在亚纳米分辨率下对材料进行三维分析，并且以前已用于研究离子注入[2]。APT将用于分析ilis辐照样品的地下化学成分。市售硅柱将用各种ILIS光束进行处理。然后用聚焦的离子束将这些柱子塑造成原子探针，APT将用于确定离子束中所含化学物质的注入深度。这项工作将进一步发展APT作为植入表征技术C . Perez-Martinez et al.， J. Vac。科学。抛光工艺。[2]李建军等，中国生物医学工程学报，2008 (5):349 - 349

This project will use atom probe tomography (APT) to study ion implantation into semiconductors with a new manufacturing and characterisation technique based on ionic liquid beams.Ionic liquids are mixtures of cations and anions without an intervening solvent. An Ionic Liquid Ion Source (ILIS) is a device in which the liquid covers a sharpened needle. The needle is subjected to electric fields to produce an ion beam. The resulting beam can be used to treat materials.ILIS provide a large variety of ion chemistries, including organic molecules, simple atomic halogens, and heavily fluorinated species. Fast etching of silicon has been demonstrated after ILIS irradiation, thanks to the reactivity of fluorinated species in the beam [1]. ILIS can be used for manufacturing (e.g. microelectronics fabrication) and in advanced characterisation of materials. The ILIS beam could be focused and used to mill materials at the nanoscale, enabling tomography or the preparation of samples for transmission electron microscopy. ILIS could also be used to perform secondary ion mass spectrometry.This project will study the implantation of ILIS ions into semiconductors, which should be understood if ILIS is used in manufacturing or characterisation. APT allows analysis of materials in three dimensions with sub-nanometer resolution, and has been used previously to study ion implantation [2]. APT will be used to profile the sub-surface chemical composition of ILIS-irradiated samples. Commercially available silicon pillars will be treated with a variety of ILIS beams. The pillars will then be shaped into atom probes using focused ion beam, and APT will be used to determine the implantation depths of chemical species contained in the ion beam. This work should further develop APT as an implantation characterisation technique.[1] C Perez-Martinez et al., J. Vac. Sci. Technol. B 28 (2010) L25[2] K Eder et al., Ultramicroscopy 228 (2021) 113334