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Semiconductor Physics, Quantum Electronics & Optoelectronics. 2005. V. 8, N 3. P. 019-024.
Morphology and optical properties of α-Si:Y films
obtained by the electron-beam evaporation method
Department of Environmental & Material Engineering,
Teikyo University of Science & Technology,
2525 Yatsusawa, Uenohara-machi, Kitatsuru-gun,
Yamanashi-pref., 409-0193 Japan
E-mail: semikina@edd.ntu-kpi.kiev.ua, tanyasemikina@rambler.ru
Abstract. This paper presents the results of AFM, Raman, IR spectroscopy and
ellipsometry of α-Si:Y films prepared by electron-beam evaporation. The influence of the
type and temperature of substrates, as well as the evaporation rate on film morphology,
composition and optical properties are studied. The evaporation rate increase allows to
enhance the growth of films on p-Si up to 0.1 μm/min. The obtained α-Si:Y films possess
an amorphous structure with a small amount of nanocrystalline inclusions. The formation
of nanocrystalline inclusions could be generated by SiHх, peaks of which are clearly
pronounced at 650, 890 and 2125 сm−1
in the IR spectrum or yttrium impurities. The
ellipsometry results show that α-Si:Y films have the high absorption coefficient,
refraction index is 3.4 at the wavelength λ = 620 nm. The optical bandgap drops from 2.0
to 1.17 eV when the substrate temperature increases (140 to 300 °С).
Keywords: α-Si:Y amorphous film, electron-beam evaporation, IR and Raman
spectroscopy, optical properties.
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