전색 HxWO3 박막의 W 4f 코어레벨의 XPS 연구

목차

I. INTRODUCTION

II. EXPERIMENTAL DETAILS

III. Results and Discussion

IV. Conclusions

ACKNOWLEDGMENTS

본문내용

and S. Hufner (North-Holland,
Amsterdam, 1987) Vol. 10, p. 103.
26. S. Doniach and M. S njic, J. Phys. C 3, 285 (1970).
27. G.K. Wertheim and P.H. Citrin, in Photoemission in Solids I, edited by M. Cardona and
L. Ley, (Springer-Verlag, New York, 1978) p.206.
28. The insulating nature of the sample might cause a broadening due to finely separated
core levels.
29. A. Flodstrom, R. Nyholm, and B. Johansson, in Synchrotron Radiation Research, Advances
in Surface and Interface Science, edited by R.Z. Bachrach (Plenum Press, New York
1992) Vol. 1, Chap. 5.
30. B.I. Min, private communications (1995). Midgap states are located near the edge of upper
conduction bands, which can be considered as virtual bound states.
31. The assumption underlying this picture is the localized nature of the O 2p states in
amorphous HxWO3 films. Considering that the O 2p electrons form a ligand in WO3, it is
reasonable to assume that they are rather localized.
32. G.K. Wertheim, L.F. Schneemeyer, and D.N.E. Buchanan, Phys. Rev. B 32, 3568 (1985).
33. Valence band PES data for amorphous HxWO3 films are not available, and so valence
band spectra amorphous LixWO3 films are presented.
34. The linewidth parameter, required to fit 5p3/2 peaks, was about 0.1 eV larger than that
for 4f peaks.
35. G.D. Mahan, Many-Particle Physics (Plenum, New York, 1986), p. 746.
36. P.H. Citrin, Phys. Rev. Lett. 31, 1164 (1973).
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TABLE I. Fitting parameters for W 4f XPS spectra. Coloration represents the amount of the injected charge density (in mC/cm2). 2γ and α represent the FWHM of the Lorentzian function and the asymmetry of core lines, respectively. ΔE denotes the energy separation between the low and high BE peaks. IL/IH denotes the intensity ratio of the low to high BE peaks.
High BE peaks (eV) Low BE Peaks (eV)
Coloration
(mC/cm2) 4f7/2 4f5/2 4f7/2 4f5/2 2γ(eV) α ΔE(eV) IL/IH
WO3
0
35.78
37.93
34.65
36.80
0.36
0.02
1.13
0.09/0.91
HxWO3
20
35.96
38.11
34.78
36.93
0.40
0.03
1.18
0.12/0.88
70
36.05
38.09
34.79
36.83
0.68
0.08
1.26
0.24/0.76
150
40.03
42.07
38.71
40.75
0.88
0.10
1.32
0.33/0.67
W metal
...
...
...
31.24
33.39
0.16
0.09
...
...

키워드

전색 HxWO3,   W4f코어레벨,   XPS연구