ELECTRODEPOSITED QUANTUM DOTS .4. EPITAXIAL SHORT-RANGE ORDER IN AMORPHOUS-SEMICONDUCTOR NANOSTRUCTURES

The structure of diffraction-amorphous CdSe (a-CdSe) quantum dots (QDs ) electrodeposited on evaporated Pd substrate was studied by high reso lution transmission electron microscopy (HRTEM), and compared with epi taxial (crystalline) QDs obtained by the same procedure on Au, as well as with a simulated image of random a-CdSe. Digital analysis of HRTEM images established the existence of repeating ordered motifs in a-CdS e QDs on Pd substrates, in the form of epitaxial sub-nanometre to nano metre size clusters. The QDs are shown to be intermediate between crys talline and random amorphous material. Digital Fourier analysis indica ted epitaxial relationship with the {111}(Pd) substrate, rotated 30 de grees relative to the orientational relationship on {111}(Au).