Fast Broadband Scanning Microwave Microscopy (FABSMM)

扫描微波显微镜（SMM）是一种多模式系统，将扫描探针显微镜（SPM）与微波测量技术相结合。从扫描探针尖端发射电磁波使得可以测量纳米级样品的电磁特性以及其形貌。宽带扫描探针显微镜（BSMM）是一种很有前途的解决方案，广泛的材料的电学分析，是这项工作的重点。在一次扫描中，可以捕获样品的电磁光谱响应。该技术还允许对样品表面以下数百纳米的结构进行无损检测。然而，目前的BSMM技术面临着两个主要挑战：1）由于热漂移和振动的时间依赖性，缓慢的扫描速度会限制纳米级的空间分辨率。因此，无法实现对生物或移动样本的准确分析。2)BSMM产生大量的测量数据：SPM地形数据，以及代表复散射参数S11的幅度和相位的两个“数据立方体”。因此，大量相关数据难以处理和解释。本项目提出的方法将使用两种不同的策略优化这些问题。首先，将结合重建算法应用改进的扫描方法。这将减少要处理的数据量并加速扫描过程。扫描技术和重建算法的最佳组合将通过比较它们的测量速度和重建质量来确定。其次，对样本进行初步调查，以确定哪些频率最相关，哪些可以忽略。最后，这两种策略将同时使用，以提高样品表征的速度，同时沿着减少测量数据和简化数据处理。在初步调查中，该基板的电磁光谱响应显示出对所测量的晶体管的pn结的非常强烈的反应。这将在项目运行期间进一步审查。这两种拟议的策略将在该测试基板上的项目期间应用和评估。因此，该项目的实施将为使用BSMM掺杂半导体提供新的见解。此外，在这个项目中开发的策略将拓宽BSMM技术的应用领域，作为测量数据量和测量速度，分别减少和增加，所提出的方法是基于以前的DFG-ANR项目的工作，其中一个单频SMM被集成到一个扫描电子显微镜的腔室，以研究阿托法拉大电容器和存储器。

Scanning Microwave Microscopy (SMM) is a multimodal system that combines Scanning Probe Microscopy (SPM) with microwave measurement technology. Emitting electromagnetic waves from a scanning probe tip makes it possible to measure electromagnetic properties of a nanoscale sample, in addition to its topography. Broadband SMM (BSMM) is a promising solution for the extensive electrical analysis of materials, and is the focus of this work. In one scan, the electromagnetic spectral response of a sample can be captured. The technique also permits non-destructive detection of structures hundreds of nanometers below a specimen’s surface. The doping concentration of semiconductors can also be determined.However, current BSMM technology is faced with to two major challenges:1) Slow scanning speeds can limit spatial resolution at the nanoscale due to the time dependency of thermal drift and vibrations. Accurate analysis of biological or moving specimens is therefore not been achieved. 2) BSMM produces a large amount of measurement data: SPM topography data, as well as two "data cubes" representing the amplitude and phase of the complex scattering parameter, S11. The large amount of correlated data is therefore difficult to process and interpret. The approach proposed in this project will optimize these issues using two different strategies. First, improved scanning methods will be applied in combination with reconstruction algorithms. This will reduce the amount of data to be processed and accelerate the scan process. The best combination of scanning techniques and reconstruction algorithms will be determined by comparing their measurement speed and reconstruction quality. Second, a preliminary investigation is undertaken on the sample in order to identifying which frequencies are most relevant, and which can be neglected. In the end, both strategies will be used simultaneously to increase the speed of sample characterization, along with a reduction in measurement data and simpler data processing.A commercially available electronic memory device from Bruker is used as a test substrate in this project. The electromagnetic spectral response of this substrate showed very strong reactions to the pn-junctions of the measured transistors, in preliminary investigations. This will be further examined during the project runtime. Both proposed strategies will be applied and evaluated during the project on this test substrate. Thus, the implementation of this project will provide new insights into doped semiconductors with the use of BSMM. In addition, the strategies developed in this project will broaden the application area of BSMM technology, as the amount of measured data and the measuring speed, is decreased and increased, respectively.The proposed method is based on previous DFG-ANR project work, where a single-frequency SMM was integrated into the chamber of a scanning electron microscope to investigate Atto-Farad large capacitors and memories.