System for angle-resolved photoelectron spectroscopy

角分辨光电子能谱系统

• 批准号: 446792822
• 金额: --
• 依托单位: Humboldt-Universität zu Berlin
• 依托单位国家: 德国
• 项目类别: Major Research Instrumentation
• 财政年份: 2021
• 资助国家: 德国
• 起止时间: 2020-12-31 至 无数据
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/446792822?language=en
• 关键词: System; angle; resolved; photoelectron; spectroscopy

To enable research at the forefront on modern and emerging materials for electronics and optoelectronics, a system for angle-resolved photoelectron spectroscopy with high spatial resolution (µ-PES) should be acquired. Of particular interest in this research field is unraveling the chemical composition and electronic properties on all relevant length scales, down to the micrometer regime. The integrated ultrahigh vacuum system, comprising sample preparation and analysis chambers, facilitates sample fabrication/preparation under highly defined conditions, analyzing the surface structure by low energy electron diffraction (LEED), determining the surface stoichiometry with X-ray photoelectron spectroscopy (XPS), as well as investigating the electronic band structure with angle-resolved ultraviolet photoelectron spectroscopy (ARUPS). A key feature of the system is that XPS and ARUPS measurements can be performed from defined sample spots, where the microscopy function of the analyzer enables selecting areas as small as a few square-micrometers. This requirement is a consequence of the current and planned research program, which encompasses materials that are characterized by heterogeneity on the micrometer length scale. This pertains to two-dimensional (2D) materials, such as transition metal dichalcogenides, transition metal carbides and nitrides, as well as conjugated 2D polymers, all often in the monolayer form. Further components of the research program, i.e., intrinsic and doped organic semiconductors, also feature spatial variations that must be identified and distinguished in experiment. The overall aim of our efforts is obtaining a comprehensive understanding of these material classes' electronic properties, which significantly contributes to their evaluation for the use in novel electronic and optoelectronic devices. The system to be acquired substantially enhances the experimental capabilities, enables exploring new research fields, and enriches our present and planned cooperations.

为了使现代和新兴的电子和光电子材料的研究处于前沿，应该获得具有高空间分辨率（µ-PES）的角度分辨光电子能谱系统。在这个研究领域，特别感兴趣的是解开所有相关长度尺度上的化学成分和电子特性，小到微米制度。集成的超高真空系统，包括样品制备室和分析室，便于在严格规定的条件下制作/制备样品，通过低能电子衍射（LEED）分析表面结构，用x射线光电子能谱（XPS）确定表面化学计量，以及用角分辨紫外光电子能谱（ARUPS）研究电子能带结构。该系统的一个关键特点是XPS和ARUPS测量可以从定义的样品点进行，其中分析仪的显微镜功能可以选择小到几平方微米的区域。这一要求是当前和计划中的研究项目的结果，该项目包括以微米长度尺度的非均匀性为特征的材料。这涉及到二维（2D）材料，如过渡金属二硫化物，过渡金属碳化物和氮化物，以及共轭二维聚合物，通常都是单层形式。研究计划的进一步组成部分，即本征和掺杂有机半导体，也具有必须在实验中识别和区分的空间变化。我们努力的总体目标是全面了解这些材料类别的电子特性，这有助于评估它们在新型电子和光电子器件中的使用。即将获得的系统大大提高了实验能力，使探索新的研究领域成为可能，并丰富了我们目前和计划中的合作。