Synthesis and Characterization of Supported CuInSe2 Nanorod Arrays on Rigid Substrates

Copper indium diselenide nanorod arrays were electrodeposited on tungsten/silicon rigid substrates using porous anodic alumina as growth template. The porous anodic alumina templates were prepared by anodizing aluminum films which were sputtered onto the tung-sten/silicon substrates. A selective chemical etching was used to penetrate the barrier layer at the bottom of the alumina channels before electrodeposition, which enables direct elec-trical and chemical contact with the underside substrate electrode. The as-deposited sam-ples were annealed at 450 oC in vacuum. Scanning electron microscopy revealed that the nanorods were dense and compact with diameter of about 100 nm, length of approximate 1 μm, and the aspect ratio of 10. X-ray diffraction, micro-Raman spectroscopy, and highresolution transmission electron microscopy showed that chalcopyrite polycrystalline struc-ture and high purity CuInSe₂ nanorods were obtained. The grain size was large in the rod axial direction. Energy-dispersive X-ray spectroscopy showed the composition was nearly stoichiometric. The energy band gap of this nanorod arrays was analyzed by fundamental absorption spectrum and was evaluated to be 0.96 eV.