2012. március 20-án (kedden) 15:30 órai kezdettel
az Atomfizikai Főosztály szemináriuma keretében
Prof. Chuhei Oshima és Prof. Yahachi Saito előadást tartanak.
Helye: ATOMKI I. épület, alagsori tanácsterem.
Minden érdeklődőt szeretettel várunk.
Kövér Ákos
főosztályvezető
Electron-spectroscopy studies of Graphene, h-BN and BC3 on solid Surface
Chuhei Oshima1
1
Department of Applied Physics, Waseda Universiy,
3-4-1 Okubo, Shinjukuku, Tokyo 169-855, Japan,
e-mail: coshima@waseda.jp
Abstract: Ultra thin films of graphene, h-BN and BC3 are grown in an epitaxial
manner to solid surfaces. We review their properties such as atomic, electronic
and lattice-dynamical structures, which are determined mainly by interface bonds
between the films and substrates、which were mainly clarified by low energy
electrons such as STM, LEED, AES, XPS, UPS and HREELS. Additionally, we
talk about in-situ observations of carpet-like growth, self-supporting film and BC3
growth by carbon segregation
Electron Microscopy Study on Carbon Nanotube as Electron Emitter and Electric Wire
Yahachi Saito
Department of Quantum Engineering, Nagoya University, Nagoya 464-8603, Japan
Carbon nanotube (CNT) is a new class of materials, possessing extraordinary properties
and propagating nanotechnology and nanoscience. One of the promising applications of such
CNTs is a tiny, nanometer-scale field electron emitter that works by applying moderate
electric voltages without heating in moderate vacuum. A field emission display (FED) is
considered to be the most influential industrial product in which the nanotechnology of CNT
is utilized as a key material. Through considerable research and development on CNT-FED,
however, it was cognized that it was not so easy to make the high-definition FED with CNT
emitters. There are still a number of technical problems to be overcome to put CNT-based
FEDs to practical use. Current reduction in retail prices of other flat panel displays such as
liquid crystal display (LCD) also makes it difficult to forward the development of FED for TV
monitor. But, CNT-based FED has great benefits of low-power consumption, and
applications of CNT electron emitters are not limited to FED; field vacuum electronic devices
such as miniature X-ray sources, electron microscopes, microwave amplifiers and so on are
also promising applications of CNT field emitters.
High current-carrying capacity exceeding a current density of 109A/cm2 without
electromigration is another merit of CNT. So, CNT is considered to be a promising as
metallic wires and interconnects in the future molecular-scale electronic devices. Such
application of CNT requires an understanding their electron transport under the high field.
In this talk, intriguing electron emission properties and dynamic behavior of CNT field
emitters revealed by field emission microscopy (FEM) and in-situ transmission electron
microscopy (TEM) as well as development of various types of CNT-based field emission
devices including FED, electron microscope and X-ray source are presented. Electrical
transport properties of CNT itself and migration of metals on the outer surface and in the
inner space of CNT, which were studied by in-situ TEM are presented.