Fabrication and analysis of the nanometer-sized structure of silicon by ultrahigh vacuum field emission transmission electron microscope

Analytical TEM observation of Au nano-particles on cerium oxide

“…Long periodicity corresponding to two-fold CeO 2 {2 0 0} and four-fold CeO 2 {2 2 0} is observed. This superstructure can be attributed to the ordered vacancies of oxygen produced by the electron beam irradiation of the usual observation condition for HRTEM, through direct knock-on by high energy electrons or electron stimulating desorption [8][9][10][11][12][13]. The structure model of ordered oxygen vacancies is represented in Fig.…”

“…It was deduced that such structural changes of Au particles depended on the changes in the oxidation state or the density of oxygen vacancies in CeO 2 support induced by electron beam irradiation. It is well-known as electron stimulated desorption that the metal oxides are reduced by electron beam irradiation with low energy [8] and high energy [9][10][11][12][13]. Although the reduction and oxidation conditions used in the catalytic reaction are quite different from the electron beam reduction in the vacuum, it is valuable to investigate the detailed structure of Au and CeO 2 depending on the oxidation state of cerium oxide.…”

Size-Dependent Stability of Supported Gold Nanostructures onto Ceria: an HRTEM Study

“…Then the stability of the gold islands onto ceria surfaces was examined using HRTEM. The high-energy electron beam naturally induces reduction conditions − as well as local changes in temperature. Behaviors of the deposited gold nanostructures were shown to be strongly dependent on their size.…”

Formation of Si Nanocrystallites in Al-Added Amorphous Si Films by Electron Beam Irradiation

“…6) It was recently reported that amorphous SiO 2 films can be dissociated to form both solid-phase Si and oxygen vapors by high-energy electron irradiation under ultra-high vacuum (UHV) conditions (<2 Â 10 À8 Pa). 7) The dissociated Si products can become either amorphous or nanocrystalline Si dots depending on the temperature of the films. The formation of such nanocrystalline Si is favorable at high temperatures.…”