MOLECULAR-BEAM EPITAXY OF CDS SELF-ASSEMBLED QUANTUM DOTS ON ZNSE

CdS quantum dot (QD) structures were grown by molecular beam epitaxy o n (001) ZnSe. Circular QDs were observed from the sample, grown at 220 degrees C, whereas rectangular QDs were observed from the sample grow n at 280 degrees C. The difference of the dot shape may be related to the metastable nature of CdS since CdS thin films grown at 220 degrees C show zincblende structures and thin films grown at 280 degrees C sh ow wurtzite structures. The PL peak position and linewidth were strong ly affected by the growth condition of QDs; QD samples with a thicker CdS deposition showed redshifts of the peak position along with the na rrowing of the linewidth. (C) 1998 American Vacuum Society.