Growth mechanism of selectively grown II-VI semiconductor photonic dots for short-wavelength light emitters

The growth mechanism of the ZnS and CdS semiconductor photonic dots grown b y metalorganic molecular-beam epitaxy (MOMBE) was studied. In the initial g rowth process, the delay time of growth initiation was present for small-ar ea ZnS selective growth. The lateral growth during the selective epitaxy wa s not linear to the growth time, which was explained by considering the dif fusion of the Zn and Cd precursors on the {0 3 4} side facets to the (0 0 1 ) top plane during the growth. The calculation of this model was in good ag reement with the experimental results. The apex of the grown structures was studied, and the apex of CdS was sharper than those of ZnS and Zn0.9Cd0.1S . This shows that it is possible to position the CdS layer which has a narr ow bandgap only on the apex of the Zn(Cd)S photonic dot as a light-emitting layer. (C) 2000 Elsevier Science B.V. All rights reserved.