Hs. Soliman et al., STRUCTURAL AND OPTICAL-PROPERTIES OF CDXZN(1-X)TE THIN-FILMS, Journal of materials science. Materials in electronics, 7(3), 1996, pp. 233-239
Seven CdxZn(1-x) Te solid solutions with x = 0.3, 0.4, 0.5, 0.6, 0.7,
0.8, 0.9 and 1.0 were synthesized by fusing stoichiometric amounts of
CdTe and ZnTe constituents in silica tubes. Each composition was used
in the preparation of a group of thin films of different thicknesses.
Structural investigation of the obtained films indicates they have a p
olycrystalline structure with predominant diffraction lines correspond
ing to (111) (220) and (311) reflecting planes, which can be attribute
d to the characteristics of growth with the (111) plane.The optical co
nstants (the refractive index n, the absorption index k, and the absor
ption coefficient alpha) of CdxZn(1-x) Te thin films were determined i
n the spectral range 500-2000 nm. At certain wavelengths it was found
that the refractive index, n, increases with increasing molar fraction
, x. It was also found that plots of alpha(2) (hv) and alpha(1/2) (hv)
yield straight lines, corresponding to direct and indirect allowed tr
ansitions respectively obeying the following two equations: E(g)(d) =
1.583 + 0.277x + 0.197x(2) E(g)(ind) = 1.281 + 0.111x + 0.302x(2).