[2015년 2학기 물리학과 콜로퀴엄 & 양자-나노 융합전공 융합세미나]
연사: 김정환 박사 (기초과학지원연구원)
제목: Development and applications of Imaging TOF-SIMS with continuous cluster ion sources
초록:
Cluster ion projectiles such as C60+ and Arn+ in SIMS imaging are able to provide an enhanced ion yield, low damage cross section and a fast erosion rate for molecular depth profiling experiments.[1] In spite of those advantages, it is not easy to use for a traditional TOF-SIMS because the beam characters are not suitable for TOF mass analyzer such as higher beam diameter and low beam current density. Here a new TOF-SIMS instrument by decoupling the mass spectrometry from secondary ion generation, the J105 chemical imager from Ionoptika, utilizes continuous cluster ion sources(C60+ and Arn+ ) and is capable of providing maximum spatial resolution and maximum mass resolution at the same time .[2, 3]
However, even the cluster ion sources exhibit surface charging due to the higher SIMS yield and higher secondary ion extraction field. To compensate for surface charging, we employ a bipolar extraction field for large bio-samples such as tissue sections and molecular films. The bipolar extraction field provides a stable SIMS signal for both C60+ and Arn+ cluster ion sources. It can lead to improved molecular depth profiling and sub-micron imaging for bio-imaging applications. The mechanism behind this unique charge compensation approach and the applications will be discussed in detail.
일시: 9월 24일 목요일 오후 4시 30분
장소: 베어드홀 103호
* 이번 세미나는 양자나노융합전공을 하는 학생들은 반드시 참석해야 되는 세미나로,
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