A self-forming diffusion barrier (SFB) layer was formed at interface. Spatial variation of the chemical composition and valence state of the elements in the SFB was investigated in a subnanometer resolution using electron energy loss spectroscopy and transmission electron microscopy. The SFB was found to have a layered structure with graded compositions of nanocrystalline MnO and amorphous . The valence state of Mn was found to be in the MnO layer and gradually increased to in the layer. The reported dielectric constant of the SFB could be explained by the observed composition and microstructure.
REFERENCES
1.
A. E.
Kaloyeros
and E.
Eisenbraun
, Annu. Rev. Mater. Sci.
30
, 363
(2000
).2.
C. J.
Liu
, J. S.
Jeng
, J. S.
Chen
, and Y. K.
Lin
, J. Vac. Sci. Technol. B
20
, 2361
(2002
).3.
J.
Koike
and M.
Wada
, Appl. Phys. Lett.
87
, 041911
(2005
).4.
K.
Barmak
, C.
Cabral
, Jr., K. P.
Rodbell
, and J. M. E.
Harper
, J. Vac. Sci. Technol. B
24
, 2485
(2006
).5.
S.
Tsukimoto
, T.
Kabe
, K.
Ito
, and M.
Murakami
, J. Electron. Mater.
36
, 258
(2007
).6.
K.
Ito
, S.
Tsukimoto
, T.
Kabe
, K.
Tada
, and M.
Murakami
, J. Electron. Mater.
36
, 606
(2007
).7.
M.
Haneda
, J.
Iijima
, and J.
Koike
, Appl. Phys. Lett.
90
, 252107
(2007
).8.
T.
Usui
, H.
Nasu
, S.
Takahashi
, N.
Shimizu
, T.
Nishikawa
, M.
Yoshimaru
, H.
Shibata
, M.
Wada
, and J.
Koike
, IEEE Trans. Electron Devices
53
, 2492
(2006
).9.
J.
Koike
, M.
Haneda
, J.
Iijima
, Y.
Otsuka
, H.
Sako
, and K.
Neishi
, J. Appl. Phys.
102
, 043527
(2007
).10.
J.
Iijima
, Y.
Fujii
, K.
Neishi
, and J.
Koike
, J. Vac. Sci. Technol. B
27
, 1963
(2009
).11.
L.
Zhao
, Zs.
Tokei
, G. G.
Gischia
, H.
Volders
, and G. P.
Beyer
, Proceedings of the 2009 International Interconnect Technologies Conference
, 2009
(unpublished), p. 206
.12.
S. M.
Chung
and J.
Koike
, J. Vac. Sci. Technol. B
27
, L28
(2009
).13.
J. M.
Ablett
, J. C.
Woicik
, Zs.
Tokei
, S.
List
, and E.
Dimasi
, Appl. Phys. Lett.
94
, 042112
(2009
).14.
R. F.
Egerton
, Electron Energy Loss Spectroscopy in the Transmission Electron Microscope
(Plenum
, New York
, 1996
).15.
D. B.
Williams
and C. B.
Carter
, Transmission Electron Microscopy
(Plenum
, New York
, 1996
).16.
H.
Kurata
and C.
Colliex
, Phys. Rev. B
48
, 2102
(1993
).17.
T.
Riedl
, T.
Gemming
, W.
Gruner
, J.
Acker
, and K.
Wetzig
, Micron
38
, 224
(2007
).18.
T.
Riedl
, T.
Gemming
, and K.
Wetzig
, Ultramicroscopy
106
, 284
(2006
).19.
L. A. J.
Garvie
and A. J.
Craven
, Ultramicroscopy
54
, 83
(1994
).20.
A. K.
Chaudhury
and K. V.
Rao
, Phys. Status Solidi B
32
, 731
(1969
).21.
22.
J. H.
Paterson
and O. L.
Krivanek
, Ultramicroscopy
32
, 319
(1990
).23.
D. B.
Loomer
, T. A.
Al
, L.
Weaver
, and S.
Cogswell
, Am. Mineral.
92
, 72
(2007
).© 2010 American Institute of Physics.
2010
American Institute of Physics
You do not currently have access to this content.
