Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign, Urbana, Illinois 61820, United States.
ACS Nano. 2012 Sep 25;6(9):8015-21. doi: 10.1021/nn302620f. Epub 2012 Aug 31.
There is a significant need for chemical identification and chemical imaging of nanofabricated structures and devices, especially for multiple materials integrated at the nanometer scale. Here we present nanofabrication, chemical identification, and nanometer-scale chemical imaging of polymer nanostructures with better than 100 nm spatial resolution. Polymer nanostructures of polyethylene, polystyrene, and poly(3-dodecylthiophene-2,5-diyl) were fabricated by tip-based nanofabrication. Nanometer-scale infrared measurements using atomic force microscopy infrared spectroscopy (AFM-IR) obtained quantitative chemical spectra of these nanostructures. We show chemical imaging of intersecting patterns of nanometer-scale polymer lines of different chemical compositions. The results indicate that for closely packed heterogeneous nanostructures, the spatial resolution of AFM-IR is not limited by nanometer-scale thermal diffusion, but is instead limited by the cantilever sensitivity and the signal-to-noise ratio of the AFM-IR system.
对于纳米制造结构和设备的化学识别和化学成像存在巨大需求,特别是对于在纳米尺度上集成的多种材料。在这里,我们展示了具有优于 100nm 空间分辨率的聚合物纳米结构的纳米制造、化学识别和纳米尺度化学成像。基于针尖的纳米制造技术制造了聚乙烯、聚苯乙烯和聚(3-十二烷基噻吩-2,5-二基)的纳米结构。使用原子力显微镜红外光谱(AFM-IR)进行纳米尺度红外测量获得了这些纳米结构的定量化学光谱。我们展示了不同化学成分的纳米尺度聚合物线相交图案的化学成像。结果表明,对于紧密堆积的异质纳米结构,AFM-IR 的空间分辨率不受纳米尺度热扩散的限制,而是受到悬臂梁灵敏度和 AFM-IR 系统的信噪比的限制。