Growth of self-organized dots of Cd1-xMnxTe on ZnTe by atomic layer epitaxy

Self-organized quantum dots (QDs) of Cd1-xMnxTe were successfully grown on the ZnTe(100) surface by atomic layer epitaxy. Atomic force microscope (AFM ) measurement revealed the dot formation in a high density on the surface o f 3.5-monolayer-thick Cd1-xMnxTe when the Mn composition x was less than 10 %. The typical dot size was 20 nm in diameter and 2 nm in height. The densi ty of dots ranged from 4 x 10(10) to 10(11) cm(-2) for x = 0-10%, but it de creased abruptly when x was more than 10%. In photoluminescence (PL) measur ements for capped QDs, excitonic luminescence from QDs was observed at 2.16 -2.27 eV depending on the Mn composition. One of the features of PL spectra from QDs containing Mn is that the spectra are composed of two PL lines wi th a separation of 20-26 meV. (C) 2000 Elsevier Science B.V. All rights res erved.