Pa. Trubenko et al., Cathodoluminescence and TEM studies of MBE-grown CdSe submonolayers in ZnSe matrix, cladded by ZnSSe, ZnSe and ZnMgSe, J CRYST GR, 214, 2000, pp. 671-675
We have studied MBE-grown CdSe submonolayers (SMLs) using cathodoluminescen
ce (CL) and transmission electron microscopy (TEM). The CdSe SMLs were embe
dded into ZnSe matrix layer and made to undergo different lattice strains f
rom thick ZnSSe, ZnSe and ZnMgSe cladding layers. It was revealed that the
CdSe SML emission line has different energy position and FWHM for the struc
tures with variable cladding layers. This characteristic is attributed to t
he effect of strain in the ZnSe matrix layer and its surface roughness on t
he CdSe distribution along the surface. At the deposition of the CdSe SMLs
on unstrained flat surface of ZnSe, the homogeneous quantum well (QW)-like
CdZnSe alloy layer is formed. Using the strained roughness surface increase
s fluctuations in the Cd distribution along the surface. While, assuming th
e compressive ZnSe matrix (ZnSSe cladding layers), the CL line has to be br
oadening for the CdSe cluster organization only, in the case of structures
with ZnMgSe cladding layers, low-energy offset is observed. This is due to
the creation of the CdSe ML islands with relatively large lateral size. (C)
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