單原子電子源與離子源之應用

Single Atom Electron and Ion Sources and Their Applications

黃英碩(Ing-Shouh Hwang) ； 郭鴻曦(Hong-Shi Kuo) ； 張哲誠(Che-Cheng Chang) ； 林君岳(Chun-Yueh Lin) ； 鄭天佐(Tien T. Tsong)

《科儀新知》 172期 (2009/10) Pp. 11-19

https://doi.org/10.29662/IT.200910.0002

摘要

貴金屬覆蓋鎢(111)單原子針可以用來做為理想的點粒子源（電子源與離子源），其製備方法簡單可靠，適合於實際運用。此單原子針有熱平衡的原子結構，化學穩定性佳，且針尖一旦受損可以在真空中加熱再生。再生的金字塔原子堆疊與第一次形成的單原子針相同。單原子針所發射出來的粒子束具有張角小、最小的發射面積、高亮度且同調性佳等特性，可以廣泛地應用在粒子束的儀器設備上。此單原子針所發射出來的粒子束，已證實其亮度與同調性較現今最佳之粒子源高數十倍甚至千倍以上。單原子針可以大幅度提昇現今的電子顯微鏡及聚焦離子束系統的效能，甚至於可開發全新功能的儀器技術，對奈米科技及基礎科學將會有許多重要的貢獻。

並列摘要

Noble-metal covered tungsten (111) single-atom tips can be used as ideal point sources of electron and ion beams. It has been shown that noble-metal covered W (111) single-atom tips can be reliably prepared and their lifetimes are long enough for real applications. These tips are both thermally and chemically stable, and can be regenerated in vacuum when accidentally damaged or contaminated. The atomic stacking remains the same each time it is regenerated. The small opening angle, smallest emitting area, high brightness, high spatial wave coherence, and high stability of these single-atom electron sources make them highly desirable for many applications. Both the brightness and spatial coherency of these electron sources are orders of magnitude better than those of the state-of-the- art electron sources used in electron microscopes. Ion beams have similar attributes also. Application of these sources may significantly improve the performance and expand the capabilities of current electron and ion microscopes, and open up many new possibilities in electron-beam and ion-beam based techniques.