Abstract
Thickness of film, energy of incident photons and glass transition temperature all affect the structural bonding between neighbours and are considered to be the main factors in studying the optical properties of amorphous selenium films. The results indicate that in the lowtemperature range (T <T g), a shift in the absorption edge to lower photon energies with increasing film thickness occurs. Increasing the thickness is accompanied by a decrease in the optical energy gap,E optg , with a gradient of 5×10−4eV nm−1. In the high-temperature range (T >T g), the value ofE optg for a given thickness decreases by more than 50% due to pronounced modulation of the structural defects under incidence of isoenergetic photons of 1.8 eV. The isothermal curves ofT,R=f(t), atT >T g, take place via three time-dependent stages. These results are interpreted and are correlated with the temperature dependence of the morphological changes declaring the formation of spherulites having a lamellar structure. The kinetic parameters controlling the structural transition are computed and the results are discussed.
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References
P. Selenyi,Nature 161 (1948) 522.
Idem, Acta Phys. 2 (1952) 129.
N. Furutra,J. Sci. Hiroshima Univ. 24 (1960) 328.
M. A. Takibi andT. M. Verdiena, “Selenium, Tellurium and their Applications”, (Acad. Sci. Azerbaijan USSR, Baka, 1965).
J. Dresner andG. B. Stringfellow,J. Phys. Chem. Solids 29 (1968) 303.
S. R. Ovshinsky andP. H. Klose,Digest Techn. Papers (1971) p. 58.
M. F. Kotkata, F. M. Ayad andM. K. Elmously,J. Non-Cryst. Solids 33 (1979) 13.
S. R. Ovshinsky andD. Adler,Contemp. Phys. 19 (1978) 109.
F. A. Abdel-Wahab, MSc thesis, Ain Shams University (1987).
L. N. Hadley, cited by Heavens, in “Physics of Thin Films”, edited by G. Hass and R. E. Thon, Vol. 2 (Academic, New York, 1964) p. 193.
S. Hasegawaa, S. Yazaki andT. Shimizu,Solid State Commun. 26 (1978) 4070.
S. Chaudhuri, S. K. Biswas, A. Choudhury andK. Goswami,J. Non-Cryst. Solids 46 (1981) 171.
S. K. J. Al-Ani andC. A. Hogarth,ibid. 69 (1984) 167.
J. P. Audiere, Ch. Mazieres andJ. C. Carbalies,ibid. 27 (1978) 411.
A. Tager, “Physical Chemistry of Polymers”, 2nd Edn (Mir, Moscow, 1978).
R. A. Westbury andW. C. Cooper, in “Selenium”, edited by R. A. Zingaro and W. Cooper, (Van Nostrand-Reinhold, New York, 1979).
M. F. Kotkata andK. M. Kandil,Mater. Sci. Engng 95 (1987) 287.
M. Avrami,J. Chem. Phys. 7 (1939) 1103.
Idem, ibid. 8 (1940) 212.
Idem, ibid. 9 (1941) 177.
M. F. Kotkata, H. A. Khalek, W. M. Atia, T. Porjesz andM. El-Samahy,J. Mater. Sci. 20 (1985) 2973.
U. R. Evans,Trans. Faraday Soc. 41 (1945) 365.
M. F. Kotkata andM. K. El-Mously,Acta Phys. Hung. 54 (1983) 303.
M. F. Kotkata, M. H. El-Fouly, A. Z. Elbehay andL. A. El-Wahab,Mater. Sci. Engng 60 (1983) 163.
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Kotkata, M.F., Abdel-Wahab, F.A. Effect of structural defects on optical properties of amorphous selenium films. J Mater Sci 25, 2379–2388 (1990). https://doi.org/10.1007/BF00638031
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DOI: https://doi.org/10.1007/BF00638031