  The influence of a distributed Bragg reflector composed of ZnTe, MgTe, and
MgSe superlattices on photoluminescence of self assembled CdTe quantum dots
(QD) emitting in the yellow spectral range is investigated. In the case of QDs
grown on a distributed Bragg reflector the photoluminescence intensity is
enhanced by more than one order of magnitude, whereas the single QD lines are
broadened as compared to the case of QDs grown on a ZnTe buffer. Structural and
chemical analysis reveal an unintentional formation of a thin ZnSe layer
induced by the growth interruption needed for the deposition of the QDs sheet.
Sharp emission lines from individual quantum dots are recovered in the case of
a thicker ZnTe layer grown prior to the QDs. This indicates that growth
interruptions might be responsible for the QD emission line broadening.
