IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Surface Science Monday Sessions
       Session SS2-MoP

Paper SS2-MoP11
Temperature Effect of Well-ordered Al@sub2@O@sub3@ Film on NiAl(110)

Monday, October 29, 2001, 5:30 pm, Room 134/135

Session: Surfaces and Interfaces Poster Session
Presenter: T.T. Lay, National Institute for Material Science, Japan
Authors: T.T. Lay, National Institute for Material Science, Japan
M. Yoshitake, National Institute for Material Science, Japan
B. Mebarki, National Institute for Material Science, Japan
Correspondent: Click to Email
It is known that the oxidation of the (110) surface of intermetallic compound NiAl leads to the formation of a well-ordered Al@sub2@O@sub3@ film.@footnote 1@ It has the potential of application in metal-insulator-metal(M-I-M) electron emitter which needs wide gap insulator. In our previous work epitaxial ultra-thin Al@sub2@O@sub3@ film was grown on NiAl(110) by introducing 1200L oxygen at 570K and subsequent annealing at 1070K. The crystalinity of the epitaxial film varied from pressure 5 x 10@super-7@ to 5 x 10@super-8@ Torr. The best crystalinity was obtained when oxygen was introduced at pressure of 5 x 10@super-8@ Torr. However, to get 1200L oxygen at 5 x 10@super-8@ Torr, the time needed is 400minutes. For thick epitaxial Al@sub2@O@sub3@ film, multi-oxidation is required and time needed to growth desire film thickness is too long. To get well-ordered thick expitaxial Al@sub2@O@sub3@ film in higher growth rate, we have carried out the temperature control in oxidation. Oxidation temperature varied from 570K to 720K at constant pressure of 5 x 10@super-7@ Torr for 1200L. After oxidation subsequent annealing is performed at 1070K in a vacuum chamber equipped with LEED/AES. From the LEED pattern, the crystalinity of epitaxial Al@sub2@O@sub3@ film become distinct as temperature increases and shows optimum at temperature around 670K. AES measurement also has good correlation with the results of LEED patterns. The ratio of O/Ni peak intensity is directly related to film thickness.@footnote 2@ The optimum ratio of O/Ni was obtained at temperature around 670K and approximately equal to several multi-oxidations at pressure 5 x 10@super-8@ Torr at 570K. The result shows crystalinity and thickness can be control by oxidation temperature. @FootnoteText@ @footnote 1@ R.M. Jaeger, H.Kuhlenbech, H.J.Freund, M.Wuttig, W. Hoffmann, R. Franchy and H. Ibach, Surf. Sci., 259,235(1991) @footnote 2@ M. Yoshitake and B. Mebarki, 6th. Int.Symposium on Advanced Physical Fields, Tsukuba, Japan, March 6-9, 183(2001)