"

Cookies ussage consent

Our site saves small pieces of text information (cookies) on your device in order to deliver better content and for statistical purposes. You can disable the usage of cookies by changing the settings of your browser. By browsing our site without changing the browser settings you grant us permission to store that information on your device.

I agree, do not show this message again.

Grain growth behavior, surface morphology evolution, structures, and optical properties of ZnO thin films prepared by RF reactive magnetron sputtering

HUI LU1,* , ZHI-JIA ZHENG1, XIAN LIN2, FEI XU1, HAN BI1, AATTO LAAKSONEN3

Affiliation

  1. Department of Physics, East China University of Science and Technology, Shanghai 200237, China
  2. Department of Physics, Shanghai University, Shanghai 200444, China
  3. Division of Physical Chemistry, Department of Materials and Environmental Chemistry, Stockholm University, S-10691 Stockholm, Sweden

Abstract

ZnO thin films were prepared by radio frequency (RF) reactive magnetron sputtering at varying deposition conditions. The effects of RF power (from 40 to 90 W) and substrate temperature (from 100 to 200 ℃) on the grain growth behavior, surface morphology evolution, and the structural and optical properties of the films were investigated. Atomic force microscopy (AFM) measurements confirmed that the grain size and surface roughness depend mainly on the RF power and increase with increasing it at the initial deposition stage of 5 s, and are strongly affected by the substrate temperature and increase with increasing it at the final deposition stage of 45 min. The influence of both the deposition parameters on the surface structure of the ZnO films at different deposition stages and the mechanism concerning this influence were discussed. The X-ray diffraction (XRD) and optical absorption spectra analysis indicated that all the films deposited for 45 min are in the state of the compressive stress and exhibit polycrystalline nature with the (002) preferential orientation, and they have high optical transparency in the visible range and sharp absorption edges around the wavelength 360 nm corresponding to the ZnO exciton. With the increase of the RF power and substrate temperature, the grain size increases, the residual compressive stress relaxes, and the optical band gaps broaden. In comparison with the RF power, the substrate temperature has more evident influence on the microstructure of the ZnO thin films..

Keywords

ZnO Thin films, RF magnetron sputtering, Deposition, Microstructure, Optical properties.

Submitted at: Sept. 17, 2012
Accepted at: Jan. 22, 2014

Citation

HUI LU, ZHI-JIA ZHENG, XIAN LIN, FEI XU, HAN BI, AATTO LAAKSONEN, Grain growth behavior, surface morphology evolution, structures, and optical properties of ZnO thin films prepared by RF reactive magnetron sputtering, Journal of Optoelectronics and Advanced Materials Vol. 16, Iss. 1-2, pp. 170-175 (2014)