TY - JOUR
T1 - Application of XPS time-dependent measurement to the analysis of charge trapping phenomena in HfAlO x films
AU - Hirose, K.
AU - Yamawaki, M.
AU - Torii, K.
AU - Kawahara, T.
AU - Kawashiri, S.
AU - Hattori, T.
N1 - Funding Information:
This work was partly supported by the ‘high-k network’ cooperating with academies, industries, and governmental institutes, and by the Ministry of Education, Science, Sports, and Culture through a Grant-in-Aid for Scientific Research C(2) (No. 15560025), B(2) (No. 16340088).
PY - 2004/10/15
Y1 - 2004/10/15
N2 - We found that the Si 2p photoelectron peak binding energy of a Si substrate covered with a 3 nm thick HfAlO X film increased to a saturation value during X-ray irradiation. This shift towards a higher binding energy indicates an increase in the amount of positive charges in the film, and the density of hole traps is estimated to be significantly higher than that in a SiO 2 film. Before X-ray irradiation, the interface Fermi level coincided with the valence-band maximum of the Si substrate, which indicates that the Si surface band bends upward. This means that there were negative charges already in the film before X-ray irradiation. Investigating the effects of the interlayer beneath the HfAlO x film on these trapped charges reveals that the observed hole trapping and initial electron trapping are intrinsic to the HfAlO x film.
AB - We found that the Si 2p photoelectron peak binding energy of a Si substrate covered with a 3 nm thick HfAlO X film increased to a saturation value during X-ray irradiation. This shift towards a higher binding energy indicates an increase in the amount of positive charges in the film, and the density of hole traps is estimated to be significantly higher than that in a SiO 2 film. Before X-ray irradiation, the interface Fermi level coincided with the valence-band maximum of the Si substrate, which indicates that the Si surface band bends upward. This means that there were negative charges already in the film before X-ray irradiation. Investigating the effects of the interlayer beneath the HfAlO x film on these trapped charges reveals that the observed hole trapping and initial electron trapping are intrinsic to the HfAlO x film.
KW - Crystalline-amorphous interfaces
KW - Hafnium oxides
KW - Insulating films
KW - Semiconductorinsulator interfaces
KW - Silicon
KW - X-ray photoelectron spectroscopy
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U2 - 10.1016/j.apsusc.2004.06.094
DO - 10.1016/j.apsusc.2004.06.094
M3 - Article
AN - SCOPUS:4644275792
VL - 237
SP - 411
EP - 415
JO - Applied Surface Science
JF - Applied Surface Science
SN - 0169-4332
IS - 1-4
ER -