Characterization of Transparent Zinc Oxide Films Prepared by Electrochemical Reaction

Abstract

Transparent zinc oxide (ZnO) films have been grown by galvanostatic cathodic deposition onto conductive glasses from a simple aqueous zinc nitrate electrolyte maintained at 335 K. The as‐deposited ZnO films were characterized with Fourier transform infrared absorption spectroscopy, x‐ray diffraction, scanning electron microscopy, optical transmission and absorption studies, and measurement of sheet resistivity as a function of cathodic current density. The ZnO films prepared had a wurtzite structure and exhibited an optical bandgap energy of 3.3 eV which is characteristic of ZnO. At a low cathodic current density of , ZnO films with excellent electrical characteristics have been obtained. A 2 μm thick ZnO film with an optical transmittance of 72% was deposited by electrolysis for approximately 20 min at a cathodic current density of .