Development of mass spectrometry for nano-area

微区分析的最新发展开始应用于测量来自小颗粒和矿物间晶界的地球化学和年代学数据。利用这些数据，我们可以阐明太阳系早期行星物质的演化过程。其中，微量同位素分析是最有力的技术手段。我们的地球科学观点正在通过这些技术发生巨大变化（Yurimoto，Kagaku 67，1997）。在微量同位素测量技术中，二次离子质谱（西姆斯）是最引人注目的。然而，目前的西姆斯方法仅限于离子探针。因此，精确的同位素比成像是困难的。在这项研究中，我们开发了新的固态离子成像器的西姆斯。我们证明，精度和空间分辨率的离子显微镜使用西姆斯耦合与新开发的固态离子成像器可以扩展到二维同位素比成像permil精度。氧同位素图清楚地揭示了4%的富集160的尖晶石颗粒嵌入黄长石从富钙铝包体的碳质球粒陨石的分布。因此，这种表征技术提供了“眼睛”，以在微观尺度上的同位素丰度的小的不均匀性。它可能在地球、材料和生命科学研究中得到广泛的应用。

Recent development of microanalysis becomes applied to measure geochemical and chronological data from small particles and from grain boundary among minerals. Using these data, we can clarify evolution process of planetary materials at early solar system. Especially, micro-isotope analysis is the most powerful technique among them. Our earth science view is drastically changing by these techniques(Yurimoto, Kagaku 67, 1997). Among the micro-isotope measurement technique, secondary ion mass spectrometry(SIMS)is most impressive. However, present SIMS method is restricted to ion microprobe. Therefore, precise isotope-ratio imaging is difficult. In this study we develop new solid-state ion imager for SIMS.We demonstrate that the precision and spatial resolution of an ion microscope using SIMS coupled with a newly developed solid-state ion imager can be extended to two-dimensional isotope ratio imaging with permil precision. An isotopic map for oxygen clearly reveals the distribution of 4%-enrichment of 160 in spinel particles embedded in melilite from a Ca-Al-rich inclusion of a carbonaceous chondrite. This characterization technique thus provides the "eyes" to e small heterogeneity of isotope abundance in micro scale. It is likely to find broad application in earth, material, and life science research.