It is crucial that functional materials, such as graphene and silicon carbide (SiC), are comprehensively characterised before they can be used in green energy applications (for example in lithium ion batteries) and as inverters for applications in automotive power control systems.
This article shows how Raman spectroscopy can be a very effective in the continuing development of functional materials. With a flexible spatial resolution—spanning from millimetre to sub-micrometre—Renishaw'sinVia Raman microscopeis a powerful and proven tool for the investigation of electronic properties, chemical properties, homogeneity, and strain in these materials.
sic晶片的特征
SIC是高功率电子产品的有前途的材料。与基于硅的设备相比，SIC设备可以在更高的温度和电压下工作，从而使它们有望在电动汽车中使用。但是，SIC的大规模增长具有挑战性，而晶片通常包含不同多型型和其他缺陷的包含，这极大地影响了最终设备的性能。
A powerful tool for characterising SiC, Raman spectroscopy is capable of distinguishing between SiC polytypes quickly and easily. It can also detect defects and determine both strain and electronic properties. Here an inVia Raman microscope, using Renishaw’s proprietary technology, characterises an entire 2” wafer in less than an hour, at a resolution of 50 µm. More than 870,000 data points were collected.
This highlights a speed increase of an order of magnitude over the past few years, thereby making it possible to perform Raman analysis on the timescales needed for the quality control of wafers. Figure 1 shows a composite Raman image.
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图1。A composite Raman image. The blue image illustrates change in peak position of the FTO Raman mode. This can be directly related to stress in the wafer. Hexagonal strain features can be seen, allowing micropipes at the centre of dislocations to be detected. The high spatial and spectral resolutions of inVia are demonstrated by the ability to image small strain features. A 6H-SiC inclusion is highlighted in red. Regions with 540nm PL, corresponding to growth defects, are shown in yellow. Inset a) spectra from the different polytypes of SiC, highlights how easy it is to differentiate polytypes using the inVia Raman microscope.
TERS Imaging on Graphene and Functionalised Carbon Nanotubes
尖端增强的拉曼光谱（TERS）集成扫描探针显微镜（SPM）和拉曼测量值，并可以在纳米量表上收集拉曼数据。
这种重要的技术适合研究纳米材料的化学性质，因为它可以以NM量表分析材料。亚博网站下载微拉曼光谱法无法通过衍射限制为横向分辨率约300nm。
石墨烯和碳纳米管（CNT）是两个重要的纳米材料，它们针对能源行业的各种应用。亚博网站下载在此分析中，将TERS技术应用于这些材料，并用于评估其同质性。亚博网站下载图2和图3显示了TER和AFM成像之间的比较。
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Figure 2.在石墨烯和功能化的CNT上进行TERS和AFM成像。A）。石墨烯（蓝色）的TER（红色）和远场拉曼光谱。这些结果证明了TER提供的信号的增强。b）图像显示了石墨烯样品的G/2D比例的子衍射极限变化。该比率用于估计CVD石墨烯厚度。在这里，该比率在10nm的长度上存在显着变化，显示了纳米级的石墨烯变化。
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Figure 3.a）CNT簇的AFM图像，此图像允许确定簇的大小，但不提供任何化学信息；b）图像突出了集群中功能化CNT的分布（红色区域包含更多功能化的CNT）。在这里，很明显，在群集中，功能化和非功能化的CNT的混合并不均匀。
结论
This article shows how Renishaw’s advanced and powerfulinVia Raman microscopecan be effectively used for determining a material’s chemical properties, from macroscale to nanoscale.
它还显示了一种强大的表面表征工具拉曼光谱法被用来表征SIC Wafers，证明其识别缺陷区域，检测多型，评估压力并检查2英寸SIC WAFER的同质性的能力。
TERS是一种创新技术，可以从纳米分辨率的样品中获取化学数据。事实证明，这对于研究石墨烯，CNT和其他新兴碳材料特别有用。亚博网站下载
此信息已从Renishaw -Raman光谱法提供的材料中采购，审查和改编。亚博网站下载
For more information on this source, please visitRenishaw - Raman Spectroscopy.