Effect of post annealing on structural and optical properties of ZnO thin films deposited by vacuum coating technique

Abstract

We report the effect of annealing temperature on structural, electrical and optical properties of polycrystalline zinc oxide thin films grown on p-type silicon (100) and glass substrates by vacuum coating technique. The XRD and AFM measurements confirmed that the thin films grown by this technique have good crystalline hexagonal wurtzite structures and homogenous surfaces. The study also reveals that the rms value of thin film roughness increases from 6 to 16 nm, the optical band gap increases from 3.05 to 3.26 eV and resistivity from 0.3 to 5 Ωcm when the post-deposition annealing temperature is changed from 400 to 600 °C. It is observed that ZnO thin film annealed at 600 °C after deposition provide a smooth and flat texture suited for optoelectronic applications. © 2009 Springer Science+Business Media, LLC.