High performance secondary ion mass spectrometry using vacuum-type electrospray droplet ion beams

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K05119
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Quantum beam science
• Research Institution: University of Yamanashi
• Principal Investigator: NINOMIYA Satoshi 山梨大学, 大学院総合研究部, 准教授 (10402976)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: イオンビーム / 真空エレクトロスプレー / 二次イオン質量分析 / 帯電液滴 / 二次イオン収率

Outline of Final Research Achievements

In secondary ion mass spectrometry (SIMS), cluster ion beams have been studied to increase sensitivities and to accomplish damage less etching for biological and polymer samples. In my laboratory, a novel massive cluster ion beam using vacuum electrospray of aqueous solutions as a beam source has been developed for SIMS. It has been found that the vacuum electrospray droplet ion (V-EDI) beams gave extremely high secondary ion yields (total number of secondary ions of a given species detected per total number of primary ions) and useful ion yields (total number of secondary ions of a given species detected per total number of molecules of the species consumed). As the size and charge distributions of the droplets contained in the V-EDI beams were unknown, several methods for evaluating them were studied. By revealing the characteristics of the V-EDI beams, it is considered that the performance of SIMS using the V-EDI beams can be further improved.

Free Research Field

量子ビーム科学

Academic Significance and Societal Importance of the Research Achievements

二次イオン質量分析(SIMS)の対象は、従来無機試料であったが、クラスタービームが一次イオンとして利用できるようになってからは有機試料の分析にも応用される。しかしながら、これまでに実用化されたクラスタービームでは有機試料を対象とするときのSIMSの感度が低いことが問題であった。本研究では真空エレクトロスプレー液滴イオン(V-EDI)ビームを用いることでSIMSの感度を2桁以上向上できることが示された。V-EDIビーム銃を市販のSIMS装置で利用できるようになれば、様々な産業分野での応用が期待される。