Fundamentals of Innovative Atomic Resolution Field Emission Microscope and Development of Low Energy Electron Microscope

2020 Fiscal Year Final Research Report

• Project/Area Number: 18H01882
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 29030:Applied condensed matter physics-related
• Research Institution: Toyota Physical and Chemical Research Institute
• Principal Investigator: Saito Yahachi 公益財団法人豊田理化学研究所, フェロー事業部門, フェロー (90144203)
• Co-Investigator(Kenkyū-buntansha): 中原 仁 名古屋大学, 工学研究科, 助教 (20293649)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: カーボンナノチューブ / ナノカーボン / 電子放出 / 電界放出 / 電界イオン顕微鏡 / 電子顕微鏡 / グラフェン

Outline of Final Research Achievements

Field emission microscopy (FEM) and field ion microscopy (FIM) observations of pentacene molecules adsorbed on a carbon nanotube (CNT) electron emitter were carried out. FEM images of pentacene molecules were thick fringes. In FIM, cocoon-shaped (allay-shaped) spots changed their positions, and paired cocoon-shaped spots in parallel each other were observed.
A low-energy projection electron microscope with a CNT emitter as a point electron source was experimentally fabricated, and microscope images of magnification of approximately 10,000 at acceleration voltages 200-300V. An evaluation of coherence of electrons emitted from CNT field emitters was tried by using an electron biprism manufactured for the present CNT-FEM apparatus.

Free Research Field

ナノサイエンス

Academic Significance and Societal Importance of the Research Achievements

カーボンナノチューブ（CNT）やグラフェンなどのナノカーボンからの電界電子放出では，炭素原子の電子軌道や吸着分子の原子分解能での観察，真空度への要求が厳しくない（通常の高真空環境でも動作可能）など，従来のタングステンなどの金属電子源での常識を覆す，特異で興味深い現象が明らかにされている。本研究では，このCNT電子源の特性を生かして，その表面に吸着した有機分子の挙動とその分子像の観察，CNTを電子源とする新しいタイプの低速投射型電子顕微鏡の試作を行い，新たな研究分野の開拓につながる知見を得た。