ON THE NATURE OF NANOMETER-SCALE ISLANDS FORMED BY CADMIUM SELENIDE DEPOSITION ON HEXAGONAL CADMIUM-SULFIDE (0001)A

Using ex situ atomic force microscopy, nanometer-scale islands were ob served on CdS(0001)A surfaces to appear after deposition of small amou nts of CdSe. The sizes of these islands are similar to those reported in atomic force microscopy (AFM) studies of uncapped CdSe/ZnSe structu res. Investigations by force modulation microscopy and photoluminescen ce spectroscopy show, however, that they are difficult to assign to a CdSe Stranski-Krastanow growth. Instead, AFM points to an onset of the island formation with the exposure of the samples to atmosphere. By u se of electron microprobe analysis, it is suggested that these islands consist of selenium. (C) 1998 American Institute of Physics. [S0003-6 951(98)02536-4].