68
3 Crystals
(a)
Cd
Zn
Se
[110]
[001]
(b)
(c)
Fig. 3.48 Schematic diagrams of zincblende Cd x Zn 1−x Te along [110] with (a) CuAu-I type ordering and (b, c) two
types of the CuPt B type ordering. Doublet periodicity is along (a) [001] and [ ¯
110], (b) [1 ¯
11] and (c) [ ¯
111]. Adapted
from [259]
Fig. 3.47, a TEM image of a Cd 0.68 Zn 0.32 Te epilayer is shown with simultaneous ordering in the CuPt
structure (doublet periodicity along [1 ¯
11] and [ ¯
111]) and in the CuAu-I structure
7 (doublet periodicity
along [001] and [ ¯
110]).
7 The CuAu-I structure has tetragonal symmetry. There exists also the CuAu-II structure that is orthorhombic.