Growth of ZnSe nano and microstructures at high vacuum by thermal evaporation

Abstract

ZnSe nano and microstructures were grown on Si substrates in high vacuum by thermal evaporation at different source temperatures ranging from 850 to 950 °C. Morphology, chemical composition and structural properties of these grown ZnSe nano and microstructures were studied using scanning electron microscope (SEM) and transmission electron microscope (TEM). SEM studies revealed that the morphology of grown structures contains nanowires, nanobelts and microcrystals. TEM studies showed that the grown nanowires and nanobelts are single crystalline in nature with growth direction along [110] of zinc blende structure. The room temperature photoluminescence (PL) spectra of these nanostructures grown at different temperatures exhibited a strong broad defect level (DL) emission peak and a weak narrow near band edge (NBE) emission peak. Further, the intensity of DL emission peak was found to increase with increase in source temperature.