Micro-sample analytical systems
Electron microscope and the related apparatus
FE-SEM is characterized by a field-emission gun and high power optics, which enables high-resolution imaging at magnifications as high as ×100,000 and stable chemical analysis even at very low accelerating voltage. It is equipped with an energy dispersive X-ray spectroscopic (EDS; dry, SDD-type) detector, an electron back scattered diffraction (EBSD) detector and a cathode luminescence detector, providing comprehensive characterization of materials recovered from high pressure experiments form various aspects.
This SEM equipped with a latest EDS detector (Oxford, X-max50) is used for phase identification, chemical and microstructure analyses of samples recovered from high pressure experiments.
This 200 kV TEM is used to analyze microtexture, crystal structure and chemical properties of minerals/materials at micro- to nano scales. It is equipped with two CCD cameras (Gatan, Orius 200D and Orius 1000 (for high-resolution imaging)) and an EDS detector for chemical analysis. Specimens are usually prepared by FIB or ion slicer or PIPS to be thin enough (< 100 nm thick), but powdered samples are also acceptable.
FIB is equipped with a Ga+ ion gun and imaging optics similar to that of SEM. It is used to cut out a thin cross-section foil (typically, 15×10×0.1μm) for TEM observation from a target area of samples recovered from high pressure experiments. It takes typically 6-8 hours to prepare one foil.
These facilities are used to coat sample surface with a thin conductive layer before SEM-EDS analysis. Three types of coating sources (C, Au and Os) are available depending on the purpose and sample conditions. The newly installed Os coater provides an extremely thin coating layer with a precise thickness by the CVD technique, which is useful for high-resolution imaging of fine surface structures and porous textures and also for chemical quantification and EBSD analyses.
・Ion slicer (JEOL, EM-09100 IS)
・Ar ion milling (PIPS)
X-ray and the other spectrometers
X-ray diffraction from the micro area of the sample can be detected by the curved imaging plate. Dual wavelengths (Cu or Mo) are available. CuKα is generally used for the reflection and the transmission measurement. MoKα enable us to measure XRD pattern of the high pressure sample in DAC due to its high penetrating power.
X-ray diffraction from the powder or thin sample can be detected by goniometer. User can choose the parallel, the focusing, and the small angle X-ray scattering geometries depending on the purpose. The scintillation counter and the 1 dimensional high-speed position sensitive detector are installed as a detector. This diffractometer is useful for the phase identification and the unit cell parameter refinement.
・Raman spectrometers (JEOL, NRS-5100；PHOTON Design, RSM 800)
・Fourier transform infrared spectrometer, FT-IR (Jasco, IRT-5200EUO)
・UV-Vis-NIR spectrophotometer (Jasco, V-670)