Spherical Spin-Coated Copper Tin Oxide Polycrystals from Inorganic Precursor: Synthesis, Surface Microstructural and Optical Characterization

Abstract

Thin film of copper doped tin oxide was deposited by spin coating technique. The Sn⁴⁺, Cu²⁺ and O^2- were sourced from tin chloride, copper nitrate and potassium hydroxide. The films growth was achieved at a constant angular speed with variation in spun period. The samples were characterized by some surface techniques. Results from scanning electron microscopy (SEM) showed that the deposited films are amorphous with distinct and evenly distributed spherical particles across the substrate. Enhancement of films crystallinity and particles agglomeration was achieved by post-annealing. Elemental constituents of the film were evidently revealed. The optical behaviour of the films revealed the absorption edge at 593 and 709 nm, respectively. The obtained optical results are generally time dependent. The estimated average energy band gap of 2.83 eV suggested the appropriateness of deposited nanostructure as transparent contact electrodes in optoelectronic applications.