부산대학교 도서관

A set of macro porous silicon (ma-PSi) substrates with various surface morphologies fabricated at various etching times was inspected as a substrate for creation of SnO2/CuO nanoparticles. Spray pyrolysis process of 0.1 M SnCl4.5H2O and 0.1 M CuCl2 with mixing concentration (70%SnO2:30%CuO) was used to create SnO2/CuO nanoparticles. The n-type PSi was fabricated in electrochemical etching method assisted with laser photonic source at various four different morphologies of ma-PSi pore-like structure, and different roughness values 17.1, 16.1, 46.9, and 32 nm were fabricated with changing the etching time 7, 14, 21, and 28 min, correspondingly. The topographical and cross-sectional morphological characteristics of substrates before and after incorporation of SnO2/CuO nanoparticles were inspected through examining of scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction (XRD) patterns. The results displayed that the SnO2/CuO nanoparticles sizes be governed by the surface topography and roughness of ma-PSi. The SnO2/CuO nanoparticles created by Spray pyrolysisprocess are governed by the porosity and the shape of pores in pore-like structure. For 35% low porosity ma-Psi of non-completely cylindrical shape, the sizes of SnO2/CuO nanoparticle were in the range from 58.3 to 63.1 nm for a low surface roughness. For 54%, 67% and 78% high porosities of ma-Psi of complete form which owns the higher pore dimension and surface roughness, SnO2/CuO nanoparticle sizes fluctuate from 65 to 70.6 nm, 23.7 to 28.9 nm and 33 to 39 nm, respectively. The lowest SnO2/CuO crystal size of about 11.5 nm and higher specific surface area were achieved from a porous surface ma-Psi of 67 % porosity. Photoluminescence showed multi peaks at visible region with the red shift as the etching time increase [ABSTRACT FROM AUTHOR]