The universal sample holders of microanalytical instruments of FIB, TEM, NanoSIMS, and STXM-NEXAFS for the coordinated analysis of extraterrestrial materials

• Published in: Earth, Planets and Space
• Main Authors: Motoo Ito, Naotaka Tomioka, Kentaro Uesugi, Masayuki Uesugi, Yu Kodama, Ikuya Sakurai, Ikuo Okada, Takuji Ohigashi, Hayato Yuzawa, Akira Yamaguchi, Naoya Imae, Yuzuru Karouji, Naoki Shirai, Toru Yada, Masanao Abe
• Format: Article in Journal/Newspaper
• Language: English
• Published: SpringerOpen 2020
• Subjects: Universal sample holder; Coordinated analysis; Hayabusa2 returned sample; Asteroid ryugu; Geography. Anthropology. Recreation; G; Geodesy; QB275-343; Geology; QE1-996.5; Antarctic; The Antarctic; Ryugu; Antarc*
• Online Access: https://doi.org/10.1186/s40623-020-01267-2; https://doaj.org/article/892c0b4653c64703900bcaea8819e87e

Abstract We developed universal sample holders [the Kochi grid, Kochi clamp, and Okazaki cell) and a transfer vessel (facility-to-facility transfer container (FFTC)] to analyze sensitive and fragile samples, such as extremely small extraterrestrial materials. The holders and container prevent degradation, contamination due to the terrestrial atmosphere (water vapor and oxygen gas) and small particles, as well as mechanical sample damage. The FFTC can isolate the samples from the effects of the atmosphere for more than a week. The Kochi grid and clamp were made for a coordinated micro/nano-analysis that utilizes a focused-ion beam apparatus, transmission electron microscope, and nanoscale secondary ion mass spectrometry. The Okazaki cell was developed as an additional attachment for a scanning transmission X-ray microscope that uses near-edge X-ray absorption fine structure (NEXAFS). These new apparatuses help to minimize possible alterations from the exposure of the samples to air. The coordinated analysis involving these holders was successfully carried out without any sample damage or loss, thereby enabling us to obtain sufficient analytical datasets of textures, crystallography, elemental/isotopic abundances, and molecular functional groups for µm-sized minerals and organics in both the Antarctic micrometeorite and a carbonaceous chondrite. We will apply the coordinated analysis to acquire the complex characteristics in samples obtained by the future spacecraft sample return mission.