Synthesis and characterization of self-assembled Cu2O nano-dots

Self-assembled Cu2O nano-dots have been synthesized on single-crystal SrTiO3 substrates using oxygen-plasma-assisted molecular beam epitaxy (OPA-MBE), and characterized using a number of different techniques including atomic force microscopy (AFM), x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD), and scanning Auger microscopy (SAM). It was found that similar to conventional semiconductor systems the growth of Cu2O nano-dots underwent shape/size transformations at different stages of growth. However, the transformations of Cu2O/SrTiO3 are more complex and involve no Cu2O wetting layer at the SrTiO3 surface, thus suggesting that the detailed mechanisms involved in shape/size transformations of Cu2O/SrTiO3 may differ from those of semiconductors.