Structural Geology, Tectonics and Geomechanics, RWTH Aachen University, Aachen, Germany.
J Microsc. 2013 Mar;249(3):215-35. doi: 10.1111/jmi.12011. Epub 2013 Jan 16.
The contribution describes the implementation of a broad ion beam (BIB) polisher into a scanning electron microscope (SEM) functioning at cryogenic temperature (cryo). The whole system (BIB-cryo-SEM) provides a first generation of a novel multibeam electron microscope that combines broad ion beam with cryogenic facilities in a conventional SEM to produce large, high-quality cross-sections (up to 2 mm(2)) at cryogenic temperature to be imaged at the state-of-the-art SEM resolution. Cryogenic method allows detecting fluids in their natural environment and preserves samples against desiccation and dehydration, which may damage natural microstructures. The investigation of microstructures in the third dimension is enabled by serial cross-sectioning, providing broad ion beam tomography with slices down to 350 nm thick. The functionalities of the BIB-cryo-SEM are demonstrated by the investigation of rock salts (synthetic coarse-grained sodium chloride synthesized from halite-brine mush cold pressed at 150 MPa and 4.5 GPa, and natural rock salt mylonite from a salt glacier at Qom Kuh, central Iran). In addition, results from BIB-cryo-SEM on a gas shale and Boom Clay are also presented to show that the instrument is suitable for a large range of sedimentary rocks. For the first time, pore and grain fabrics of preserved host and reservoir rocks can be investigated at nm-scale range over a representative elementary area. In comparison with the complementary and overlapping performances of the BIB-SEM method with focused ion beam-SEM and X-ray tomography methods, the BIB cross-sectioning enables detailed insights about morphologies of pores at greater resolution than X-ray tomography and allows the production of large representative surfaces suitable for FIB-SEM investigations of a specific representative site within the BIB cross-section.
该贡献描述了将宽束离子束（BIB）抛光机集成到在低温下运行的扫描电子显微镜（SEM）中的实现。整个系统（BIB-低温-SEM）提供了第一代新型多束电子显微镜，它将宽束离子束与低温设备结合在传统 SEM 中，以在低温下生成大尺寸、高质量的横截面（最大 2mm²），并以最先进的 SEM 分辨率进行成像。低温方法允许在其自然环境中检测流体，并防止样品干燥和脱水，这可能会损坏天然微观结构。通过连续切片实现对三维微观结构的研究，提供了厚度可达 350nm 的宽束离子束断层扫描。通过对岩盐（由卤石盐水冷压在 150MPa 和 4.5GPa 下合成的粗粒合成氯化钠和来自伊朗中部 Qom Kuh 盐冰川的糜棱岩盐）的研究，证明了 BIB-低温-SEM 的功能。此外，还展示了 BIB-低温-SEM 在泥页岩和 Boom Clay 上的结果，以表明该仪器适用于广泛的沉积岩。首次可以在 nm 范围内对保存的宿主和储层岩石的孔隙和颗粒结构进行研究，代表了一个基本区域。与聚焦离子束-SEM 和 X 射线断层扫描方法的互补和重叠性能相比，BIB 切片能够以比 X 射线断层扫描更高的分辨率详细了解孔隙的形态，并允许生成大的代表性表面，适用于 FIB-SEM 对 BIB 切片中特定代表性部位的研究。
